Schedule of Unaudited pro Forma Financial Information from Joint Venture (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Business Acquisition, Pro Forma Information [Line Items]
Revenues	$ 1,036,245	$ 1,009,234	$ 1,740,222	$ 1,663,275
Net income	60,428	59,583	73,601	74,937
Less: net income attributable to noncontrolling interest	21,629	21,059	26,710	27,355
Net income attributable to Watsco, Inc.	$ 38,799	$ 38,524	$ 46,891	$ 47,582
Diluted earnings per share for Common and Class B common stock	$ 1.13	$ 1.12	$ 1.36	$ 1.39

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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