Consolidated Statement of Changes In Shareholders' Equity (USD $) In Millions, except Share data, unless otherwise specified		Total	Preferred stock	Common Stock	Additional Paid-in capital	Retained Earnings	Accumulated other comprehensive income (loss)	Comprehensive income
Beginning balance at Dec. 31, 2008			$ 1,565	$ 0	$ 11,694	$ 245	$ (787)
Beginning balance, shares at Dec. 31, 2008			25,947,600	709
Capital contributions from parent					2,167
Return of capital on preferred shares issued to CT Financial Services, Inc.					(55)
Employee benefit plans and other					(11)
Adjustment to initially apply new guidance for other-than-temporary impairment on debt securities, net of tax						15	(15)
Balance at beginning of period, as adjusted						260	(802)
Cash dividends declared on preferred stock						(73)
Net change in unrealized gains (losses), net of tax as applicable on:
Securities available-for-sale, not other-than-temporarily impaired							444
Other-than-temporarily impaired debt securities available for sale (1)	[1]						(41)
Derivatives classified as cash flow hedges							171
Other comprehensive income, net of tax							574	574
Comprehensive income
Net income (loss)		(142)				(142)		(142)
Other comprehensive income, net of tax							574	574
Comprehensive income								432
Shares redeemed			(100)
Number of shares of common stock issued to parent				3
Ending balance at Dec. 31, 2009		15,177	1,565	0	13,795	45	(228)
Ending balance, shares at Dec. 31, 2009			25,947,500	712
Return of capital on preferred shares issued to CT Financial Services, Inc.					(3)
Employee benefit plans and other					(7)
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						(74)
Net change in unrealized gains (losses), net of tax as applicable on:
Securities available-for-sale, not other-than-temporarily impaired							165
Other-than-temporarily impaired debt securities available for sale (1)	[1]						55
Other-than-temporarily impaired debt securities held to maturity (1)	[1]						93
Derivatives classified as cash flow hedges							13
Unrecognized actuarial gains, transition obligation and prior service costs relating to pension and postretirement benefits, net of tax							(5)
Other comprehensive income, net of tax							321	321
Comprehensive income
Net income (loss)		1,564				1,564		1,564
Other comprehensive income, net of tax							321	321
Comprehensive income								1,885
Shares redeemed			0
Number of shares of common stock issued to parent				0
Ending balance at Dec. 31, 2010		16,733	1,565	0	13,785	1,536	(153)
Ending balance, shares at Dec. 31, 2010			25,947,500	712
Capital contributions from parent					21
Employee benefit plans and other					8
Balance at beginning of period, as adjusted						1,536	(153)
Cash dividends declared on preferred stock						(73)
Net change in unrealized gains (losses), net of tax as applicable on:
Securities available-for-sale, not other-than-temporarily impaired							786
Other-than-temporarily impaired debt securities available for sale (1)	[1]						1
Other-than-temporarily impaired debt 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 classified as cash flow hedges							(142)
Unrecognized actuarial gains, transition obligation and prior service costs relating to pension and postretirement benefits, net of tax							(3)
Other comprehensive income, net of tax							795	795
Comprehensive income
Net income (loss)		1,018				1,018		1,018
Other comprehensive income, net of tax							795	795
Comprehensive income								1,813
Shares redeemed			0
Number of shares of common stock issued to parent				0
Ending balance at Dec. 31, 2011		$ 18,502	$ 1,565	$ 0	$ 13,814	$ 2,481	$ 642
Ending balance, shares at Dec. 31, 2011			25,947,500	712

[1] During 2011, there were no other-than-temporary ("OTTI") losses on securities recognized in other revenues and no OTTI losses on securities were recognized in the non-credit component in accumulated other comprehensive income (loss) ("AOCI"), net of tax. During 2010, other-than-temporary impairment OTTI losses on securities available-for-sale and held-to-maturity totaling $79 million were recognized in other revenues and losses in the non-credit component recognized in AOCI, net of tax were not significant. During 2009, $208 million of OTTI losses on securities available-for-sale were recognized, of which $84 million was recognized in AOCI, net of tax.