75000 - Document - Cover Page link:presentationLink link:calculationLink link:definitionLink 75010 - Statement - Condensed Consolidated Unaudited Statements of Income link:presentationLink link:calculationLink link:definitionLink 75020 - Statement - Condensed Consolidated Unaudited Statements of Comprehensive Income link:presentationLink link:calculationLink link:definitionLink 75030 - Statement - Condensed Consolidated Unaudited Balance Sheets link:presentationLink link:calculationLink link:definitionLink 75040 - Statement - Condensed Consolidated Unaudited Balance Sheets (Parenthetical) link:presentationLink link:calculationLink link:definitionLink 75050 - Statement - Condensed Consolidated Unaudited Statements of Shareholders' Equity link:presentationLink link:calculationLink link:definitionLink 75060 - Statement - Condensed Consolidated Unaudited Statements of Shareholders' Equity (Parenthetical) link:presentationLink link:calculationLink link:definitionLink 75070 - Statement - Condensed Consolidated Unaudited Statements of Cash Flows link:presentationLink link:calculationLink link:definitionLink 995455 - Disclosure - BASIS OF PRESENTATION link:presentationLink link:calculationLink link:definitionLink 995465 - Disclosure - REVENUES link:presentationLink link:calculationLink link:definitionLink 995475 - Disclosure - EARNINGS PER SHARE link:presentationLink link:calculationLink link:definitionLink 995485 - Disclosure - OTHER COMPREHENSIVE INCOME (LOSS) link:presentationLink link:calculationLink link:definitionLink 995495 - Disclosure - ACQUISITIONS link:presentationLink link:calculationLink link:definitionLink 995505 - Disclosure - DERIVATIVES link:presentationLink link:calculationLink link:definitionLink 995515 - Disclosure - FAIR VALUE MEASUREMENTS link:presentationLink link:calculationLink link:definitionLink 995525 - Disclosure - SHAREHOLDERS' EQUITY link:presentationLink link:calculationLink link:definitionLink 995535 - Disclosure - COMMITMENTS AND CONTINGENCIES link:presentationLink link:calculationLink link:definitionLink 995545 - Disclosure - RELATED PARTY TRANSACTIONS link:presentationLink link:calculationLink link:definitionLink 995555 - Disclosure - SEGMENT REPORTING link:presentationLink link:calculationLink link:definitionLink 995565 - Disclosure - SUBSEQUENT EVENTS link:presentationLink link:calculationLink link:definitionLink 995575 - Disclosure - BASIS OF PRESENTATION (Policies) link:presentationLink link:calculationLink link:definitionLink 995585 - Disclosure - REVENUES (Tables) link:presentationLink link:calculationLink link:definitionLink 995595 - Disclosure - EARNINGS PER SHARE (Tables) link:presentationLink link:calculationLink link:definitionLink 995605 - Disclosure - OTHER COMPREHENSIVE INCOME (LOSS) (Tables) link:presentationLink link:calculationLink link:definitionLink 995615 - Disclosure - FAIR VALUE MEASUREMENTS (Tables) link:presentationLink link:calculationLink link:definitionLink 995625 - Disclosure - Basis of Presentation - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 995635 - Disclosure - Revenues - Summary of Disaggregated Revenue (Detail) link:presentationLink link:calculationLink link:definitionLink 995645 - Disclosure - Earnings Per Share - Schedule of Basic and Diluted Earnings per Common Share (Detail) link:presentationLink link:calculationLink link:definitionLink 995655 - Disclosure - Earnings Per Share - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 995665 - Disclosure - Other Comprehensive Income (Loss) - Schedule of Accumulated Other Comprehensive Loss (Detail) link:presentationLink link:calculationLink link:definitionLink 995675 - Disclosure - Acquisitions - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 995685 - Disclosure - Derivatives - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 995695 - Disclosure - Fair Value Measurements - Assets and Liabilities Carried at Fair Value Measured on Recurring Basis (Detail) link:presentationLink link:calculationLink link:definitionLink 995705 - Disclosure - Fair Value Measurements - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 995715 - Disclosure - Shareholders' Equity - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 995725 - Disclosure - Commitments and Contingencies - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 995735 - Disclosure - Related Party Transactions - Additional Information (Detail) link:presentationLink link:calculationLink link:definitionLink 995745 - Disclosure - Segment Reporting - Additional Information (Details) link:presentationLink link:calculationLink link:definitionLink Common And Class B Common Stock [Member] Common And Class B Common Stock [Member] Common and Class B Common Stock [Member] Proceeds from Sale of Property, Plant, and Equipment Proceeds from sale of property and equipment Concentration Risk Type [Axis] Concentration Risk Type [Axis] Entity Incorporation, State or Country Code Balance Sheet Location [Domain] Balance Sheet Location [Domain] Related and Non related Parties [Axis] Equity [Abstract] Entity Current Reporting Status Available for sale under AT-the-Market offering program. Available For Sale Under Atm Offering Program Available for sale under ATM Program Fair Value, Inputs, Level 2 [Member] Fair Value Measurements, Level 2 [Member] Stock Issuances From Exercise Of Stock Options And Employee Stock Purchase Plan Value Stock Issuances From Exercise Of Stock Options And Employee Stock Purchase Plan Value Stock issuances from exercise of stock options and employee stock purchase plan Commitments and Contingencies Disclosure [Text Block] COMMITMENTS AND CONTINGENCIES Earnings Per Share, Basic [Abstract] Basic Earnings per Share: Product and Service [Axis] Document Fiscal Period Focus Revenue from Contract with Customer [Abstract] Entity Shell Company Dividends, Common Stock, Cash Dividends declared and paid on common stock Participating Securities, Distributed and Undistributed Earnings (Loss), Diluted Less: distributed and undistributed earnings allocated to restricted common stock Short-Term Investments [Member] Short-term cash investments [Member] Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents Common Stock, Shares, Issued Number of shares sold and issued under ATM Asset Class [Domain] Statement [Table] Statement [Table] Long-term Debt and Capital Lease Obligations [Abstract] Long-term obligations: Agreement. Agreement [Axis] Payments to Acquire Businesses, Gross Cash consideration for business acquisition Hawkins HVAC Distributors Inc [Member] Statement [Line Items] Statement [Line Items] Business Acquisition, Acquiree [Domain] Percentage of sales revenues from product lines. Sales Revenues From Product Lines Percentage Revenues from product lines, percentage Entity Filer Category Liabilities and Equity Total liabilities and shareholders' equity Foreign Currency Contract, Asset, Fair Value Disclosure Derivative financial instruments Related and Non related Parties [Domain] Goodwill Goodwill Stock Option [Member] Geographical [Domain] Stockholders Equity Note [Line Items] Stockholders Equity Note [Line Items] Stockholders Equity Note [Line Items] Maximum aggregate offering amount of stock. Maximum Aggregate Offering Amount Of Stock Maximum aggregate offering amount of stock Derivative Instruments and Hedging Activities Disclosures [Line Items] Derivative Instruments and Hedging Activities Disclosures [Line Items] Additional Paid in Capital, Common Stock Paid-in capital Private Equities Fv Ni. Private Equities Fv Ni Private equity securities Related Party [Member] Stock Issued During Period, Value, Dividend Reinvestment Plan Dividend reinvestment plan Disaggregation of Revenue [Table] Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Schedule of Basic and Diluted Earnings Per Common Share Increase (Decrease) in Other Operating Assets and Liabilities, Net Other, net Investment, Name [Axis] Earnings Per Share, Basic Basic Basic earnings per share for common stock Summary of Disaggregated Revenue Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Other comprehensive income (loss), net of tax Foreign currency translation adjustment Liabilities, Current Total current liabilities Increase (Decrease) in Accounts Receivable Accounts receivable, net Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net income to net cash provided by operating activities: Stock Issued During Period, Value, Restricted Stock Award, Forfeitures Forfeitures of restricted shares of common stock Stockholders' Equity Attributable to Parent [Abstract] Watsco, Inc. shareholders' equity: Entity Small Business Carrier and Its Affiliates Carrier and Its Affiliates [Member] Carrier and Its Affiliates [Member] Retained Earnings (Accumulated Deficit) Retained earnings Other Current Assets [Member] Other Current Assets [Member] Purchases of short-term cash investments Payments to Acquire Short-Term Investments Organization, Consolidation and Presentation of Financial Statements [Abstract] Basis of Presentation [Abstract] Weighted Average Number Diluted Shares Outstanding Adjustment Effect of dilutive stock options Amendment Flag Event basis Event Basis [Domain] Product and Service [Domain] Maturities of certificates of deposit Maturities of Certificates of Deposit Maturities of certificates of deposit. Liabilities and Equity [Abstract] LIABILITIES AND SHAREHOLDERS' EQUITY Entity Address, Postal Zip Code Net Cash Provided by (Used in) Operating Activities Net cash provided by operating activities Common Stock [Member] Common Stock [Member] Common Stock [Member] Entity Address, Address Line One Program name. Program Name [Axis] Fair Value Hierarchy and NAV [Axis] Fair Value, Hierarchy [Axis] Earnings Per Share [Abstract] Earnings per share for Common and Class B common stock (collectively "common stock"): Supplemental Cash Flow Information [Abstract] Supplemental cash flow information: Balance Sheet Location [Axis] Balance Sheet Location [Axis] Operating Lease, Right-of-Use Asset Operating lease right-of-use assets Net Income (Loss) Attributable to Noncontrolling Interest Less: net income attributable to non-controlling interest Document Type 2021 ATM program. Two Thousand Twenty One ATM Program [Member] 2021 ATM Program [Member] Gross Profit Gross profit Entity Central Index Key Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Net (decrease) increase in cash and cash equivalents Percentage of Controlling Ownership In Joint Venture Percentage of controlling ownership in joint venture. Percentage of ownership in joint venture Subsequent Event Type [Domain] Anti-dilutive stock options not included above Anti-dilutive stock options not included above Stock Repurchased and Retired During Period, Shares Retirement of common stock (in shares) Common Stock, Par or Stated Value Per Share Common stock, par value Operating lease liabilities net of current portion. Operating Lease Liabilities Net Of Current Portion Operating lease liabilities, net of current portion Accumulated Foreign Currency Adjustment Attributable to Parent [Member] Foreign Currency Translation Adjustment [Member] Derivative, Notional Amount Notional value of derivatives Accrued Liabilities, Current Accrued expenses and other current liabilities Stock Issued During Period, Value, Restricted Stock Award, Gross Issuances of restricted shares of common stock Ownership [Domain] Current Fiscal Year End Date Document Quarterly Report Entity Address, State or Province Investment, Name [Domain] Business acquisition goodwill acquired expected period of tax deduction. Business Acquisition Goodwill Acquired Expected Period Of Tax Deduction Businesss acquistion goodwill expected period of tax deduction Comprehensive Income (Loss), Net of Tax, Attributable to Parent Comprehensive income attributable to Watsco, Inc. Geographical [Axis] Shares Paid for Tax Withholding for Share Based Compensation Shares withheld as payment for tax withholdings related to share based compensation, shares Stockholders' Equity Attributable to Noncontrolling Interest Non-controlling interest Other HVAC Product. Other HVAC Products [Member] Other HVAC Product [Member] W.L. Lashley Associates, Inc [Member] Other Assets, Noncurrent Other assets Related Party Transaction [Axis] Related Party Transaction [Axis] AOCI Attributable to Parent [Member] Accumulated Other Comprehensive Loss [Member] Concentration risk threshold percentage. Concentration Risk Threshold Percentage Percentage of purchases from key suppliers Stock Issued During Period, Shares, Treasury Stock Reissued Net proceeds from the sale of Common stock (in shares) Common Stock Class B Common Stock And Preferred Stock [Member] Common Stock Class B Common Stock And Preferred Stock [Member] Common Stock, Class B Common Stock and Preferred Stock [Member] Preferred Stock, Value, Issued Preferred stock, $0.50 par value Selling, General and Administrative Expense Selling, general and administrative expenses Income Tax. Basis Of Presentation [Line Items] Basis of Presentation [Line Items] Minimum [Member] Assets, Current [Abstract] Current assets: Common Class B [Member] Class B Common Stock [Member] Fair Value, Inputs, Level 3 [Member] Fair Value Measurements, Level 3 [Member] Segment Reporting [Abstract] Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Assets and Liabilities Measured at Fair Value on Recurring Basis Liabilities, Current [Abstract] Current liabilities: Stock Repurchased and Retired During Period, Value Retirement of common stock Related Party Transactions [Abstract] Shares, Outstanding Ending balance (in shares) Beginning balance (in shares) Accounts Receivable, Net, Current Accounts receivable, net Commitments and Contingencies Commitments and contingencies Provision for Doubtful Accounts Provision for doubtful accounts Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Stock Issued During Period, Value, Treasury Stock Reissued Net proceeds from the sale of Common stock Joint Venture [Domain] Class B common stock securities that may be converted to Common stock securities at any time on a one-for-one basis at the option of the shareholder. Convertible Class B Common Stock Outstanding Class B common stock conversion, number of shares Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations Effect of foreign exchange rate changes on cash and cash equivalents Interest Income (Expense), Net Interest income, net Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Net income Net income Net income AOCI Including Portion Attributable to Noncontrolling Interest, before Tax Ending balance Beginning balance Weighted Average Number of Shares Outstanding, Basic Weighted-average common shares outstanding - Basic Weighted-average common shares outstanding - Basic Document Information [Line Items] Earnings Per Share [Table] Earnings Per Share [Table] Earnings Per Share [Table] Cost of Goods, Total [Member] Cost of Goods, Total [Member] Supplier Concentration Risk [Member] Supplier Concentration Risk [Member] Segment Reporting, Expense Information Used by CODM, Description Subsequent Events [Text Block] SUBSEQUENT EVENTS Related Party Transactions Disclosure [Text Block] RELATED PARTY TRANSACTIONS Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Share-based compensation Stockholders' Equity Attributable to Parent Total Watsco, Inc. shareholders' equity Preferred Stock, Par or Stated Value Per Share Preferred stock, par value Foreign Currency Contracts, Liability, Fair Value Disclosure Derivative financial instruments Statement of Stockholders' Equity [Abstract] Short-Term Cash Investments [Policy Text Block] Short-Term Cash Investments. Short-Term Cash Investments Equity Method Investments Investment in unconsolidated entity Program name. Program Name [Domain] Business acquisition annual sales. Business Acquisition Annual Sales Annual sales Use of Estimates, Policy [Policy Text Block] Use of Estimates Investments, Fair Value Disclosure [Abstract] Assets: Treasury Stock, Common [Member] Treasury Stock [Member] OCI, before Reclassifications, Net of Tax, Attributable to Parent Current period other comprehensive income (loss) Entity Address, Address Line Two Fair Value Disclosures [Text Block] FAIR VALUE MEASUREMENTS Amount of non-cash discretionary contribution made by an employer to a defined contribution plan. Non Cash Contribution To 401 K Plan Non-cash contribution to 401(k) plan Derivative, Maturity Month and Year. Derivative Maturity Month and Year Contract expiring terms Commercial Refrigeration Products. Commercial Refrigeration Products [Member] Commercial Refrigeration Products [Member] UNITED STATES United States [Member] Noncontrolling Interest [Member] Non-controlling Interest [Member] Other Assets, Current Other current assets Income (Loss) from Equity Method Investments Other income Other income from investment in unconsolidated entity Dividend Reinvestment Plan [Member] Derivative Instruments and Hedging Activities Disclosure [Abstract] Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration] Cumulative value of common stock sold under the 2021 ATM program. Cumulative Value Of Common Stock Sold Under The 2021 ATM Program Cumulative value of Common Stock sold under the 2021 ATM Program Available for issuance under the dividend reinvestment plan. Available For Issuance Under The Dividend Reinvestment Plan Authorized shares of each of Common and Class B available for issuance under the Dividend Reinvestment Plan Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Entity [Domain] Entity [Domain] Credit Facility [Axis] Equity Method Investment, Ownership Percentage Percentage of equity method investment Cost of Goods and Services Sold Cost of sales Certificates of Deposit [Member] Treasury Stock, Value Treasury stock, at cost Proceeds from Issuance of Common Stock, Dividend Reinvestment Plan Proceeds from Dividend Reinvestment Plan Related Party Transactions By Related Party [Axis] Entity Address, City or Town Deferred Income Taxes and Other Liabilities, Noncurrent Deferred income taxes and other liabilities Number of Reportable Segments Number of reportable segment Security Exchange Name Credit Facility [Domain] Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Income before income taxes Concentration Risk Type [Domain] Concentration Risk Type [Domain] Stockholders Equity Note [Table] Stockholders Equity Note [Table] Stockholders Equity Note [Table] Inventory, Net Inventories, net Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents Cash and cash equivalents at end of period Cash and cash equivalents at beginning of period Range [Domain] Agreement. Agreement [Domain] Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net Gain (loss) from foreign currency forward and option contracts not designated as hedging instruments Assets, Current Total current assets Document Period End Date Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy [Domain] Gain (Loss) on Disposition of Property Plant Equipment Loss on sale of property and equipment Participating Securities, Distributed and Undistributed Earnings (Loss), Basic Less: distributed and undistributed earnings allocated to restricted common stock Statement of Financial Position [Abstract] Stock issuances from exercise of stock options and employee stock purchase plan. Stock Issuances From Exercise Of Stock Options And Employee Stock Purchase Plan Shares Stock issuances from exercise of stock options and employee stock purchase plan (in shares) Class of Stock [Axis] Class of Stock [Axis] Equity Method Investments [Policy Text Block] Equity Method Investments Restricted Stock [Member] Restricted Stock [Member] Income Tax. Income Tax [Table] Weighted Average Number of Shares Outstanding, Diluted Weighted-average common shares outstanding - Diluted Weighted-average common shares outstanding - Diluted Entity File Number Payments of Ordinary Dividends, Common Stock Dividends on common stock Cover [Abstract] Increase (Decrease) in Accounts Payable and Accrued Liabilities Accounts payable and other liabilities Business combination recognized identifiable assets acquired and liabilities assumed intangible assets including goodwill. Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Intangible Assets Including Goodwill Goodwill acquired Derivative Instruments and Hedging Activities Disclosures [Table] Derivative Instruments and Hedging Activities Disclosures [Table] Earnings per share disclosures. Earnings Per Share [Line Items] Earnings Per Share [Line Items] Number of operating segment Number of Operating Segments Segment Reporting Disclosure [Text Block] SEGMENT REPORTING Stock Issued During Period, Shares, Acquisitions Common stock issued (in shares) Greenberg Traurig, P. A. Greenberg Traurig, P. A. Member Greenberg Traurig, P.A. [Member] Foreign Exchange Forward Contracts And Not Designated As Hedging Instrument Economic Hedge [Member] Foreign exchange forward contracts and not designated as hedging instrument economic hedge. Foreign Exchange Forward Contracts and Not Designated as Hedging Instrument Economic Hedge [Member] Recently Adopted Accounting Standards and Recently Issued Accounting Standards Not Yet Adopted Recently Issued Accounting Standards Not Yet Adopted Ownership [Axis] Comprehensive Income (Loss) Note [Text Block] OTHER COMPREHENSIVE INCOME (LOSS) Financial Liabilities Fair Value Disclosure [Abstract] Liabilities: Commercial specialists inc. Commercial Specialists Inc [Member] Commercial Specialists, Inc., [Member] Depreciation, Depletion and Amortization Depreciation and amortization Document Transition Report Short-Term Investments Short-term cash investments Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Comprehensive income Statement of Cash Flows [Abstract] Payments to Acquire Businesses, Net of Cash Acquired Business acquisitions, net of cash acquired Stockholders' Equity Note Disclosure [Text Block] SHAREHOLDERS' EQUITY Proceeds from non controlling interest for investment in consolidated entity Proceeds From Non Controlling Interest For Investment In Consolidated Entity Proceeds from non-controlling interest for Business Acquisition Earnings Per Share [Text Block] EARNINGS PER SHARE No Of Locations From where this enterprise carries out its operations. Number Of Locations In Which The Entity Operates Number of locations in which the company operates Net income attributable to Watsco, Inc. Net income attributable to Watsco, Inc. shareholders Increase (Decrease) in Inventories Inventories, net New Accounting Pronouncement Standards. New Accounting Pronouncement Standards [Policy Text Block] Recently Adopted Accounting Standards Joint Venture [Axis] Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items] Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items] Intangible Assets, Net (Excluding Goodwill) Intangible assets, net Carrier Enterprise I, [Member] Carrier Enterprise I, [Member] Payments of Ordinary Dividends, Noncontrolling Interest Distributions to non-controlling interest Net repayments of finance lease liabilities. Net Repayments Of Finance Lease Liabilities Net repayments of finance lease liabilities Assets [Abstract] ASSETS Repayments of Debt Repayment of indebtedness Document Fiscal Year Focus Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Schedule of Accumulated Other Comprehensive Loss Other Assets [Member] Other assets [Member] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Net Cash Provided by (Used in) Investing Activities [Abstract] Cash flows from investing activities: Accounts Payable, Current Accounts payable H V A C Equipment Product [Member] HVAC Equipment Product. HVAC Equipment [Member] United States Joint Ventures with Carrier Corp. and its Affiliates [Member] United states joint ventures with carrier corp. and its affiliates. U.S. Joint Ventures with Carrier Corp. and its Affiliates [Member] Proceeds from Stock Options Exercised Cash received from the exercise of stock options Fair Value Disclosures [Abstract] Commitments and Contingencies Disclosure [Abstract] CANADA Canada [Member] Stock Issued During Period, Value, Acquisitions Common stock issued Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Repayments of Long-Term Lines of Credit Net repayments under revolving credit agreement Net Income (Loss) Available to Common Stockholders, Basic Earnings allocated to Watsco, Inc. shareholders - Basic Earnings allocated to Watsco, Inc. shareholders - Basic Derivative Instrument [Axis] Derivative Instrument [Axis] Proceeds, Issuance of Shares, Share-Based Payment Arrangement, Excluding Option Exercised Proceeds from issuances of Common stock under employee related plans Long-term Debt and Capital Lease Obligations, Current Current portion of lease liabilities Revenues Revenues Net Cash Provided by (Used in) Investing Activities Net cash provided by (used in) investing activities Direct costs. Direct Costs Direct costs Title of 12(b) Security Derivative Instruments and Hedging Activities Disclosure [Text Block] DERIVATIVES Related and Nonrelated Parties [Domain] 2024 ATM program. Two Thousand Twenty Four ATM Program [Member] 2024 ATM Program [Member] Accounts Payable [Member] Document Information [Table] Customary Fees for Legal Services [Member] Customary Fees for Legal Services [Member] Customary Fees for Legal Services [Member] Legal Entity [Axis] Legal Entity [Axis] Increase (Decrease) in Operating Capital [Abstract] Changes in operating assets and liabilities, net of effects of acquisitions: Contribution from non controlling interest for investment in consolidated entity. Contribution From Non Controlling Interest For Investment In Consolidated Entity Investment in Lashley Proceeds from Issuance of Shares under Incentive and Share-based Compensation Plans, Including Stock Options Net proceeds from shares purchased under ESPP Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Business Combination Disclosure [Text Block] ACQUISITIONS Additional Paid-in Capital [Member] Paid-In Capital [Member] Trading Symbol Schedule of Related Party Transactions, by Related Party [Table] Schedule of Related Party Transactions, by Related Party [Table] Equity Securities, FV-NI Equity securities Extinguishment of Debt [Axis] Subsequent Event Type [Axis] Certificates of Deposit, at Carrying Value Certificates of deposit Net Cash Provided by (Used in) Financing Activities [Abstract] Cash flows from financing activities: Equity Components [Axis] Equity Components [Axis] Event basis Event Basis [Axis] Equity Component [Domain] Equity Component [Domain] Asset Class [Axis] Foreign exchange forward and option contracts and Not designated as hedging instrument economic hedge. Foreign Exchange Forward And Option Contracts and Not Designated As Hedging Instrument Economic Hedge [Member] Foreign Exchange Forward And Option Contracts and Not Designated As Hedging Instrument Economic Hedge [Member] Southern Ice Equipment Distributors, Inc. Southern Ice Equipment Distributors, Inc. [Member] Proceeds from Noncontrolling Interests Proceeds from non-controlling interest for investment in Lashley Controlling interest percentage. Controlling Interest Percentage Business Acquisition [Axis] Canadian Joint Venture with Carrier Corp and its Affiliates [Member] Canadian Joint Venture with Carrier Corp and its Affiliates [Member] Statement of Comprehensive Income [Abstract] Maximum [Member] Statistical Measurement [Axis] Common Stock, Value, Issued Common stock Investment Maturity Period Investment maturity period. Investment maturity period Net Income (Loss) Available to Common Stockholders, Diluted Earnings allocated to Watsco, Inc. shareholders - Diluted Earnings allocated to Watsco, Inc. shareholders - Diluted Russell Sigler, Inc. [Member] Russell Sigler, Inc. Basis of Consolidation Basis of Consolidation Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Ending balance Beginning balance Total shareholders' equity Related Party Transaction, Amounts of Transaction Fees for related party transaction Stock Issued During Period, Value, Employee Benefit Plan Common stock contribution to 401(k) plan Proceeds from Sale of Treasury Stock Net proceeds from the sale of Common stock Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest Less: comprehensive income attributable to non-controlling interest Payments Related to Tax Withholding for Share-based Compensation Shares withheld as payment for tax withholdings related to share based compensation, market value Repurchases of common stock to satisfy employee withholding tax obligations Latin America and Caribbean [Member] Latin America and Caribbean [Member] Latin America and the Caribbean [Member] Related Party Transaction [Line Items] Related Party Transaction [Line Items] Revenue from Contract with Customer [Text Block] REVENUES Business Combination [Table] Entity Registrant Name Proceeds from Sale of Short-Term Investments Proceeds from maturities of short-term cash investments Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Subsequent Events [Abstract] Income Tax Expense (Benefit) Income taxes Common Stock, Dividends, Per Share, Cash Paid Cash dividends paid per share of common stock Non controlling interest percentage. Non Controlling Interest Percentage Employee Stock Purchase Plan [Member] Entity Common Stock, Shares Outstanding Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated other comprehensive loss, net of tax Payments to Acquire Property, Plant, and Equipment Capital expenditures Assets Total assets Income Statement [Abstract] Deferred Income Tax Expense (Benefit) Deferred income tax provision Earnings Per Share, Diluted [Abstract] Diluted Earnings per Share: Business Combination [Abstract] Earnings Per Share, Diluted Diluted Diluted earnings per share for common stock City Area Code Other Comprehensive Income (Loss), Net of Tax Other comprehensive income (loss) Finance Lease, Liability, Noncurrent Finance lease liabilities, net of current portion Business Acquisition [Line Items] Stock Issued During Period, Shares, Restricted Stock Award, Gross Issuances of restricted shares of common stock (in shares) Number of joint ventures. Joint ventures are entities operated by the controlling interest for the mutual benefit of the members. Number of Joint Ventures Number of U.S. Joint Ventures Business Combination, Consideration Transferred, Equity Interests Issued and Issuable Business combination shares issued Fair value of equity shares issued or issuable Property, Plant and Equipment, Net Property and equipment, net Operating Income (Loss) Operating income Retained Earnings [Member] Retained Earnings [Member] Stock Issued During Period, Shares, Employee Benefit Plan Common stock contribution to 401(k) plan (in shares) Share-based Compensation Share-based compensation Long-term Debt and Capital Lease Obligations Total long-term obligations Fair Value, Inputs, Level 1 [Member] Fair Value Measurements, Level 1 [Member] Net Cash Provided by (Used in) Financing Activities Net cash used in financing activities Extinguishment of Debt, Type [Domain] Derivative Contract [Domain] Derivative Contract [Domain] Accrued Expenses and Other Current Liabilities [Member] Accrued Expenses and Other Current Liabilities [Member] Accrued expenses & other current liabilities [Member] Entity Interactive Data Current Net Cash Provided by (Used in) Operating Activities [Abstract] Cash flows from operating activities: Business Acquisition, Equity Interest Issued or Issuable, Number of Shares Stock issued for acquisition Common Stock, Dividends, Per Share, Declared Cash dividends declared and paid, common stock Entity Tax Identification Number BASIS OF PRESENTATION Local Phone Number Related Party Transaction [Domain] Related Party Transaction [Domain] Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Other Liabilities, Current Amount payable to related party Cash Acquired from Acquisition Cash acquired Accounting Policies [Abstract] Stock Issued During Period, Shares, Dividend Reinvestment Plan Stock issued during period, shares, dividend reinvestment plan Dividend reinvestment plan (in shares) Disaggregation of Revenue [Line Items] Stock Issued During Period, Shares, Restricted Stock Award, Forfeited Forfeitures of restricted shares of common stock (in shares) Schedule of Earnings Per Share, Basic, by Common Class, Including Two Class Method [Table] Schedule of Earnings Per Share, Basic, by Common Class, Including Two Class Method [Table] Class of Stock [Domain] Class of Stock [Domain] Self Insurance Reserve Self-insurance reserves Entity Emerging Growth Company