Commitments and Contingencies Outstanding Commitments to Extend Credit and Letters of Credit (Details) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Residential Mortgage Principal Balance Repurchase Request Received	$ 500,000	$ 8,800,000
Residential Mortgage, Settlement Agreement, Amount	4,500,000
Residential Mortgage, Settlement Agreement Resulting in Reduction to Outstanding Repurchase Request	7,500,000
Residential Mortgage, Settlement Agreement Resulting in Reduction to Reserves for Repurchase	5,100,000
Decrease in Operating Risk Loss	600,000
Residential Mortgage Principal Balance FHLB Credit Enhancement	175,000,000
Residential Mortgage Repurchase Reserves FHLB Credit Enhancement	3,200,000	3,600,000
Commitments to Extend Credit [Member] | Reserve for Off-balance Sheet Activities [Member]
Valuation allowances and Reserves, Balance	4,258,552,000	4,379,578,000
Standby Letters of Credit [Member] | Reserve for Off-balance Sheet Activities [Member]
Valuation allowances and Reserves, Balance	387,424,000	391,445,000
Commercial Letters of Credit [Member] | Reserve for Off-balance Sheet Activities [Member]
Valuation allowances and Reserves, Balance	35,404,000	36,344,000
Residential Mortgage [Member] | Reserve for Off-balance Sheet Activities [Member]
Valuation allowances and Reserves, Balance	$ 3,600,000	$ 8,600,000