Commitments and Contingencies Outstanding Commitments to Extend Credit and Letters of Credit (Details) (Reserve for Off-balance Sheet Activities [Member], USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Commitments to Extend Credit [Member]
Valuation allowances and Reserves, Balance	$ 3,856,706	$ 3,780,824
Standby Letters of Credit [Member]
Valuation allowances and Reserves, Balance	443,144	489,097
Commercial Letters of Credit [Member]
Valuation allowances and Reserves, Balance	25,256	31,388
Residential Mortgage [Member]
Valuation allowances and Reserves, Balance	$ (1,500)	$ (3,300)