Acquisitions (Schedule Of Unaudited Pro Forma Financial information From Joint Venture) (Details) (USD $) In Thousands, except Per Share data	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Acquisitions [Abstract]
Revenues	$ 914,039	$ 874,899	$ 2,384,314	$ 2,344,465
Net income	51,818	46,182	114,702	101,972
Less: net income attributable to noncontrolling interest	18,271	13,958	38,180	30,326
Net income attributable to Watsco, Inc.	$ 33,547	$ 32,224	$ 76,522	$ 71,646
Diluted earnings per share for Common and Class B common stock	$ 1.02	$ 0.99	$ 2.32	$ 2.21

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.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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