Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

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Derivatives and Balance Sheet Offsetting (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Derivative [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	$ 4	$ (8)
Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement	46,914
Secured Borrowings, Gross, Difference, Amount	0
U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member]
Derivative [Line Items]
Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement	46,914
Maturity Overnight [Member] \| U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member]
Derivative [Line Items]
Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement	21,914
Maturity Less than 30 Days [Member] \| U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member]
Derivative [Line Items]
Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement	0
Maturity 30 to 90 Days [Member] \| U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member]
Derivative [Line Items]
Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement	0
Maturity Greater than 90 Days [Member] \| U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member]
Derivative [Line Items]
Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement	25,000
Not Designated as Hedging Instrument [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Derivative, Notional Amount	336,100		$ 309,300
Not Designated as Hedging Instrument [Member] \| Other Assets [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Fair value of asset derivative instruments	8,598		9,012
Not Designated as Hedging Instrument [Member] \| Other Liabilities [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Fair value of liability derivative instruments	$ 8,618		$ 9,036