Unconsolidated Entities - Other Joint Ventures, Investment in and Advances to by Region (Parenthetical) (Detail) (USD $)	12 Months Ended	3 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Jun. 30, 2012 Other joint ventures [Member]	Dec. 31, 2012 Other joint ventures [Member]
Schedule of Equity Method Investments [Line Items]
Return of capital	$ 291,679,000	$ 170,158,000	$ 220,195,000	$ 95,000,000
Amount for dissolution investment					$ 80,800,000

Cash dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporations that are returns of capital. Excludes dividends or distributions from equity method investments classified as operating activities.

No definition available.

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