Consolidated Statement of Changes in Shareholders' Equity (Unaudited) (USD $) In Millions, unless otherwise specified									6 Months Ended
	Jun. 30, 2012 Preferred stock	Dec. 31, 2011 Preferred stock	Jun. 30, 2011 Preferred stock	Dec. 31, 2010 Preferred stock	Jun. 30, 2012 Common Stock	Dec. 31, 2011 Common Stock	Jun. 30, 2011 Common Stock	Dec. 31, 2010 Common Stock	Jun. 30, 2012 Additional Paid-in capital	Jun. 30, 2011 Additional Paid-in capital	Jun. 30, 2012 Retained Earnings	Jun. 30, 2011 Retained Earnings	Jun. 30, 2012 Accumulated other comprehensive income (loss)	Jun. 30, 2011 Accumulated other comprehensive income (loss)
Beginning balance	$ 1,565	$ 1,565	$ 1,565	$ 1,565					$ 13,814	$ 13,785	$ 2,481	$ 1,536	$ 642	$ (153)
Capital contributions from parent										21
Employee benefit plans and other									(24)
Net income (loss)											(310)	561
Cash dividends declared on preferred stock											(37)	(36)
Other comprehensive income, net of tax													122	281
Total shareholders' equity	$ 1,565	$ 1,565	$ 1,565	$ 1,565					$ 13,790	$ 13,806	$ 2,134	$ 2,061	$ 764	$ 128