Disclosure of Changes in Number of Shares (Detail)	6 Months Ended			12 Months Ended
	Jun. 30, 2011	Jun. 30, 2010		Dec. 31, 2010
Treasury stock	(223,532)	(182,431)		(201,356)
Common Stock - Outstanding	1,023,977,895	1,022,695,797		1,022,727,802
Common Stock
Beginning balance	1,022,929,158	639,544,895		639,544,895
Issuance of stock	1,272,269			50,930
Conversion of stock		383,333,333	[1]	383,333,333	[1]
Ending balance	1,024,201,427	1,022,878,228		1,022,929,158
Preferred Stock
Beginning balance		2,006,391		2,006,391
Issuance of stock		1,150,000		1,150,000	[1]
Conversion of stock		(1,150,000)		(1,150,000)	[1]
Ending balance	2,006,391	2,006,391		2,006,391

[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).