Disclosure of Changes in Number of Shares (Parenthetical) (Detail)	6 Months Ended		12 Months Ended
	Jun. 30, 2010		Dec. 31, 2010
Depositary shares issued			46,000,000
Common Stock
Conversion of shares into common shares	383,333,333	[1]	383,333,333	[1]

[1] Issuance of 46,000,000 in depositary shares; converted into 383,333,333 common shares (full conversion of depositary shares, each representing a 1/40th interest in shares of contingent convertible perpetual non-cumulative preferred stock).