Basic and Diluted Earnings Per Common Share (Detail) (USD $) In Thousands, except Share data	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Basic Earnings Per Common Share:
Net income attributable to Redwood	$ 9,439	$ 28,601	$ 27,604	$ 75,444
Net income allocated to common shareholders	9,247	27,806	26,875	73,333
Basic weighted average common shares outstanding	78,324,057	77,800,642	78,176,767	77,739,279
Basic Earnings Per Common Share	$ 0.12	$ 0.36	$ 0.34	$ 0.94
Diluted Earnings Per Common Share:
Net income attributable to Redwood	9,439	28,601	27,604	75,444
Net income allocated to common shareholders	9,096	27,916	26,682	73,734
Basic weighted average common shares outstanding	78,324,057	77,800,642	78,176,767	77,739,279
Net effect of dilutive equity awards	1,153,447	1,051,617	1,248,593	922,363
Diluted weighted average common shares outstanding	79,477,504	78,852,259	79,425,360	78,661,642
Diluted Earnings Per Common Share	$ 0.11	$ 0.35	$ 0.34	$ 0.94
Basic Earnings (Loss) Per Common Share
Basic Earnings Per Common Share:
Less: Dividends and undistributed earnings allocated to participating securities	192	795	729	2,111
Diluted Earnings Per Common Share:
Less: Dividends and undistributed earnings allocated to participating securities	192	795	729	2,111
Diluted Earnings (Loss) Per Common Share
Basic Earnings Per Common Share:
Less: Dividends and undistributed earnings allocated to participating securities	343	685	922	1,710
Diluted Earnings Per Common Share:
Less: Dividends and undistributed earnings allocated to participating securities	$ 343	$ 685	$ 922	$ 1,710

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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