Fair Value Measurements Assets and Liabilities Measured at Fair Value on a Non-recurring Basis (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Assets and Liabilities Measured at Fair Value on a Non-recurring Basis
Loans held for sale	$ 161,662	$ 156,423
Mortgage servicing rights	59,733	60,145
Fair Value, Inputs, Level 1 [Member]
Assets and Liabilities Measured at Fair Value on a Non-recurring Basis
Loans held for sale	0	0
Fair Value, Inputs, Level 2 [Member]
Assets and Liabilities Measured at Fair Value on a Non-recurring Basis
Loans held for sale	161,662	156,423
Fair Value, Inputs, Level 3 [Member]
Assets and Liabilities Measured at Fair Value on a Non-recurring Basis
Loans held for sale	0	0
Fair Value, Measurements, Nonrecurring [Member]
Assets and Liabilities Measured at Fair Value on a Non-recurring Basis
Loans held for sale	161,662	156,423
Impaired Loans	93,580	83,956
Mortgage servicing rights	64,026	66,342
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 1 [Member]
Assets and Liabilities Measured at Fair Value on a Non-recurring Basis
Loans held for sale	0	0
Impaired Loans	0	0
Mortgage servicing rights	0	0
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 2 [Member]
Assets and Liabilities Measured at Fair Value on a Non-recurring Basis
Loans held for sale	161,662	156,423
Impaired Loans	0	0
Mortgage servicing rights	0	0
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets and Liabilities Measured at Fair Value on a Non-recurring Basis
Loans held for sale	0	0
Impaired Loans	93,580	83,956
Mortgage servicing rights	$ 64,026	$ 66,342