Consolidated Statement of Changes In Shareholders' Equity (Unaudited) (USD $) In Millions		Total	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Comprehensive Income [Member]
Balance at the beginning of period at Dec. 31, 2009			$ 1,565	$ 0	$ 13,795	$ 45	$ (228)
Return of capital on preferred shares issued to CT Financial Services, Inc.					(3)
Employee benefit plans and other					(6)
Adjustment to initially apply new guidance for consolidation of VIEs, net of tax						1	(246)
Balance at beginning of period, as adjusted						46	(474)
Cash dividends declared on preferred stock						(55)
Net change in unrealized gains (losses), net of tax as applicable on:
Securities available-for-sale, not other-than-temporarily impaired							881
Other-than-temporarily impaired securities available for sale (1)	[1]						56
Other-than-temporarily impaired securities held to maturity (1)	[1]						49
Derivatives designated as cash flow hedges							10
Unrecognized actuarial gains, transition obligation and prior service costs relating to pension and postretirement benefits, net of tax							(2)
Other comprehensive income, net of tax							994	994
Total shareholders' equity		17,133	1,565		13,786	1,262	520
Comprehensive income
Net income		1,271				1,271		1,271
Other comprehensive income, net of tax							994	994
Comprehensive income								2,265
Balance at the end of period at Sep. 30, 2010		17,133	1,565		13,786	1,262	520
Balance at the beginning of period at Jun. 30, 2010
Net change in unrealized gains (losses), net of tax as applicable on:
Total shareholders' equity		17,133	1,565
Comprehensive income
Net income		417
Balance at the end of period at Sep. 30, 2010		17,133	1,565
Balance at the beginning of period at Dec. 31, 2010		16,733	1,565	0	13,785	1,536	(153)
Capital contributions from parent					21
Employee benefit plans and other					18
Balance at beginning of period, as adjusted						1,536	(153)
Cash dividends declared on preferred stock						(55)
Net change in unrealized gains (losses), net of tax as applicable on:
Securities available-for-sale, not other-than-temporarily impaired							797
Other-than-temporarily impaired securities available for sale (1)	[1]						1
Other-than-temporarily impaired securities held to maturity (1)	[1]						11
Adjustment to reverse other-than-temporary impairment on securities held-to-maturity due to deconsolidation of VIE							142
Derivatives designated as cash flow hedges							(141)
Unrecognized actuarial gains, transition obligation and prior service costs relating to pension and postretirement benefits, net of tax							2
Other comprehensive income, net of tax							812	812
Total shareholders' equity		18,402	1,565		13,824	2,354	659
Comprehensive income
Net income		873				873		873
Other comprehensive income, net of tax							812	812
Comprehensive income								1,685
Balance at the end of period at Sep. 30, 2011		18,402	1,565		13,824	2,354	659
Balance at the beginning of period at Jun. 30, 2011
Net change in unrealized gains (losses), net of tax as applicable on:
Total shareholders' equity		18,402	1,565
Comprehensive income
Net income		311
Balance at the end of period at Sep. 30, 2011		$ 18,402	$ 1,565

[1] During the three and nine months ended September 30, 2011 there were no OTTI losses on securities recognized in other revenues and no OTTI losses in the non-credit component on securities were recognized in accumulated other comprehensive income (loss). During the three and nine months ended September 30, 2010, OTTI losses on securities available-for-sale and held-to-maturity totaling $4 million and $45 million, respectively, were recognized in other revenues and losses in the non-credit component recognized in accumulated other comprehensive income (loss) were not significant.