Schedule of Unaudited pro Forma Financial Information from Joint Venture (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Business Acquisition, Pro Forma Information [Line Items]
Revenues	$ 1,020,859	$ 1,013,864	$ 2,761,081	$ 2,677,139
Net income	59,531	58,553	133,052	133,490
Less: net income attributable to noncontrolling interest	18,526	22,063	45,236	49,418
Net income attributable to Watsco, Inc.	$ 41,005	$ 36,490	$ 87,816	$ 84,072
Diluted earnings per share for Common and Class B common stock	$ 1.19	$ 1.06	$ 2.59	$ 2.46

The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Name Statement of Financial Accounting Standard (FAS)

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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