Consolidated Statement of Comprehensive Income (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Consolidated Statement of Comprehensive Income [Abstract]
Net income	$ 206,463	$ 206,273
Other comprehensive income, net of tax and reclassification adjustments:
Net unrealized gains on investment securities	20,082	5,658
Reclassification to income for amortization of gains on terminated cash flow hedges	(70)	(70)
Foreign currency translation adjustment	402
Defined benefit plans liability adjustment	4,769	2,111
Total other comprehensive income	25,183	7,699
Total comprehensive Income	$ 231,646	$ 213,972