Consolidated Statements of Comprehensive Income (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Net income (loss)	$ 865	$ 932	$ 584
Other comprehensive income (loss), net of tax:
Net unrealized gains (losses) on securities available for sale, net of income taxes of ($58), $46, and $69	(98)	77	116
Net unrealized gains (losses) on derivative financial instruments, net of income taxes of $12, ($6), and ($63)	20	(10)	(106)
Foreign currency translation adjustments, net of income taxes	10	(4)	4
Net pension and postretirement benefit costs, net of income taxes	(28)	(74)	(28)
Total other comprehensive income (loss), net of tax	(96)	(11)	(14)
Comprehensive income (loss)	769	921	570
Less: Comprehensive income attributable to noncontrolling interests	7	12	30
Comprehensive income (loss) attributable to Key	$ 762	$ 909	$ 540