Mortgage Servicing Rights and Mortgage Servicing Activity (Changes in the Carrying Amount of Mortgage Servicing Rights) (Details) (USD $)	3 Months Ended			12 Months Ended
	Mar. 31, 2015		Mar. 31, 2014	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor Servicing Assets or Liabilities Impact of Twenty Five Percent Adverse Change in Prepayment Speed	$ 1,510,000
Mortage Servicing Rights Amortized Value [Roll Forward]
Mortgage Servicing Rights Beginning of Period	22,011,000		22,760,000	22,760,000
Mortgage Servicing Rights Additions	470,000		564,000
Amortization of Mortgage Servicing Rights (MSRs)	991,000		(855,000)
Mortgage Servicing Rights, End of Period	21,490,000		22,469,000	22,011,000
Mortage Servicing Rights Valuation Rollforward [Roll Forward]
Mortgage Servicing rights Valuation Allowance Beginning of Period	955,000		282,000	282,000
Mortgage Servicing Rights (MSR) Impairment (Recovery)	(176,000)		143,000	(700,000)
Mortgage Servicing rights Valuation Allowance, End of Period	1,131,000		425,000	955,000
Mortgage Servicing Rights Net Carrying balance	20,359,000		22,044,000	21,100,000
Fair Value of Mortgage Servicing Rights	20,526,000	[1]	22,631,000	21,228,000	[1]
Fair Value, Inputs, Level 3
Mortage Servicing Rights Valuation Rollforward [Roll Forward]
Fair Value of Mortgage Servicing Rights	20,526,000		22,631,000	21,228,000
Residential Mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Servicing Asset	$ 2,600,000,000		$ 2,700,000,000

[1] (2) MSRs with a recorded investment of $21.5 million were reduced by a specific valuation allowance totaling $1.1 million to a reported carrying value of $20.4 million resulting in recognition of $0.2 million in expense included in loan sales and servicing income in the three months ended March 31, 2015.