Computation of Net Income (Loss) Per Common Share ("EPS"), Basic and Diluted (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
Schedule of Earnings Per Share, Basic and Diluted, by Common Class [Line Items]
Net income (loss)	$ 110,685	$ (44,489)		$ 120,817	$ (129,544)
Preferred stock dividends	(931)			(1,861)
Deemed dividend on preferred stock		(191,667)	[1]		(191,667)	[1]
Net income (loss) applicable to common stock	$ 109,754	$ (236,156)		$ 118,956	$ (321,211)
Average common shares outstanding	1,021,225,911	853,010,208		1,021,380,199	746,598,082
Average potential dilutive common shares	670,230			1,162,996
Average common shares outstanding - assuming dilution	1,021,896,141	853,010,208		1,022,543,195	746,598,082
Basic and dilutive EPS	$ 0.11	$ (0.28)		$ 0.12	$ (0.43)

[1] Non-cash beneficial conversion, resulting from the conversion of contingently convertible perpetual non-cumulative preferred stock into shares of the Corporation's common stock. The beneficial conversion was recorded as a deemed dividend to the preferred stockholders reducing retained earnings, with a corresponding offset to surplus (paid in capital), and thus did not affect total stockholders' equity or the book value of the common stock.