Unaudited Pro Forma Financial Information from Joint Venture (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2012
Business Acquisition, Pro Forma Information [Line Items]
Revenues	$ 703,977
Net income	13,106
Less: net income attributable to noncontrolling interest	4,850
Net income attributable to Watsco, Inc.	$ 8,256
Diluted earnings per share for Common and Class B common stock	$ 0.21

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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-Name Statement of Financial Accounting Standard (FAS)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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