Goodwill and Other Intangible Assets (Details) (USD $) In Thousands	9 Months Ended
Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2010
Goodwill by business segment
Beginning Balance	$ 444,268		$ 444,268
Other adjustments	0
Ending Balance	444,268		444,268
Summary of other intangible assets
Total other intangible assets, gross carrying amount	506,584	506,584	506,584
Total other intangible assets, accumulated amortization	(318,107)	(277,964)	(262,918)
Total other intangible assets, net of carrying value	188,477	228,620	243,666
Estimated amortization expense of other intangible assets
2011	13,188
2012	46,075
2013	40,511
2014	35,858
2015	19,758
2016	6,606
Regional & Commercial Banking [Member]
Goodwill by business segment
Beginning Balance	16,169
Other adjustments	0
Ending Balance	16,169
WGH [Member]
Goodwill by business segment
Beginning Balance	98,951
Other adjustments	0
Ending Balance	98,951
AFCRE [Member]
Goodwill by business segment
Beginning Balance	0
Other adjustments	0
Ending Balance	0
Treasury Other [Member]
Goodwill by business segment
Beginning Balance	42,324
Other adjustments	0
Ending Balance	42,324
Retail & Business Banking [Member]
Goodwill by business segment
Beginning Balance	286,824
Other adjustments	0
Ending Balance	286,824
Core deposit intangible [Member]
Summary of other intangible assets
Total other intangible assets, gross carrying amount	376,846	376,846	376,846
Total other intangible assets, accumulated amortization	(252,397)	(219,311)	(206,658)
Total other intangible assets, net of carrying value	124,449	157,535	170,188
Customer relationship [Member]
Summary of other intangible assets
Total other intangible assets, gross carrying amount	104,574	104,574	104,574
Total other intangible assets, accumulated amortization	(40,993)	(34,751)	(32,579)
Total other intangible assets, net of carrying value	63,581	69,823	71,995
Other [Member]
Summary of other intangible assets
Total other intangible assets, gross carrying amount	25,164	25,164	25,164
Total other intangible assets, accumulated amortization	(24,717)	(23,902)	(23,681)
Total other intangible assets, net of carrying value	$ 447	$ 1,262	$ 1,483

The accumulated amount of amortization of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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