Consolidated Statements of Changes in Equity (Unaudited) (USD $) In Millions, except Share data in Thousands	Total	Preferred Stock	Series B Preferred Stock	Common Stock	Common Stock Warrant	Capital Surplus	Retained Earnings	Retained Earnings Series A Preferred Stock	Retained Earnings Series B Preferred Stock	Treasury Stock, at Cost	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interests
Beginning Balance at Dec. 31, 2010		$ 2,737		$ 946	$ 87	$ 3,711	$ 5,557			$ (1,904)	$ (17)	$ 257
Beginning Balance, Preferred Shares at Dec. 31, 2010		2,930
Beginning Balance, Common Shares at Dec. 31, 2010				880,608
Net income (loss)	271						263
Net unrealized gains (losses) on securities available for sale, net of income taxes of ($12) and ($6) for three months ended March 31, 2011 and 2012 respectively	(20)										(20)
Net unrealized gains (losses) on derivative financial instruments, net of income taxes of ($5) and $7 for three months ended March 31, 2011 and 2012 respectively	(8)										(8)
Net distribution to noncontrolling interests												15
Foreign currency translation adjustments	9										9
Net pension and postretirement benefit costs, net of income taxes	1										1
Total comprehensive income (loss) attributable to Key	268
Deferred compensation						(5)
Cash dividends declared on common shares ($0.01 per share) ($.03 per share) for three months ended March 31, 2011 and 2012 respectively								(9)
Cash dividends declared on Preferred Stock								(6)	(31)
Preferred Stock- TARP redemption, shares		(25)
Preferred Stock- TARP redemption, value		(2,451)					(49)
Amortization of discount on Series B Preferred Stock			4						(4)
Common shares issuance, Value				71		529
Common shares issuance, shares				70,621
Common shares reissued for stock options and other employee benefit plans						(68)				81
Common shares reissued for stock options and other employee benefit plans, Shares				2,697
Other		1
Ending Balance at Mar. 31, 2011	9,697	291		1,017	87	4,167	5,721			(1,823)	(35)	272
Ending Balance, Preferred Shares at Mar. 31, 2011		2,905
Beginning Balance at Dec. 31, 2011	9,922	291		1,017		4,194	6,246			(1,815)	(28)	17
Beginning Balance, Preferred Shares at Dec. 31, 2011		2,905
Beginning Balance, Common Shares at Dec. 31, 2011				953,008
Net income (loss)	200						200
Net unrealized gains (losses) on securities available for sale, net of income taxes of ($12) and ($6) for three months ended March 31, 2011 and 2012 respectively	(11)										(11)
Net unrealized gains (losses) on derivative financial instruments, net of income taxes of ($5) and $7 for three months ended March 31, 2011 and 2012 respectively	12										12
Foreign currency translation adjustments	6										6
Net pension and postretirement benefit costs, net of income taxes	2										2
Total comprehensive income (loss) attributable to Key	209
Deferred compensation						4
Cash dividends declared on common shares ($0.01 per share) ($.03 per share) for three months ended March 31, 2011 and 2012 respectively							(29)
Cash dividends declared on Preferred Stock								(6)
Common shares reissued for stock options and other employee benefit plans						(82)				98
Common shares reissued for stock options and other employee benefit plans, Shares				3,094
Ending Balance at Mar. 31, 2012	$ 10,116	$ 291		$ 1,017		$ 4,116	$ 6,411			$ (1,717)	$ (19)	$ 17
Ending Balance, Preferred Shares at Mar. 31, 2012		2,905