Consolidated Statements of Changes in Equity (Parenthetical) (USD $) In Millions, except Per Share data, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Income taxes effect on net unrealized (losses) gains on securities available for sale	$ (87)	$ (31)
Income taxes effect on net unrealized gains (losses) on derivative financial instruments	(23)	5
Cash dividends declared on common shares, per share	$ 0.105	$ 0.080
Retained Earnings [Member]
Cash dividends declared on common shares, per share	$ 0.105	$ 0.08
Retained Earnings [Member] | Series A Preferred Stock [Member]
Cash dividends declared on Preferred Stock, per share	$ 3.875	$ 3.875
Accumulated Other Comprehensive Income (Loss) [Member]
Income taxes effect on net unrealized (losses) gains on securities available for sale	(87)	(31)
Income taxes effect on net unrealized gains (losses) on derivative financial instruments	$ (23)	$ 5