Joint Ventures - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2012 Entity	Mar. 31, 2011
Schedule of Equity Method Investments [Line Items]
Number of joint ventures that are 50% owned	2
Equity income related to joint ventures	$ 657	$ 1,428

This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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+ Details