Derivatives and Hedging Activities (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Derivative Liability [Abstract]
Derivative liability, collateral	$ 8,800	$ 1,300
Fair value of derivative instruments	11,500	1,600
Not Designated as Hedging Instrument
Derivative Asset [Abstract]
Notional Amount	404,928	139,337
Fair Value	12,621	1,916
Derivative Liability [Abstract]
Notional Amount	370,477	125,526
Fair Value	12,551	1,898
Not Designated as Hedging Instrument \| Customer derivatives – interest rate swaps
Derivative Asset [Abstract]
Notional Amount	369,623	124,627
Fair Value	12,550	1,895
Derivative Liability [Abstract]
Notional Amount	369,623	124,627
Fair Value	12,549	1,895
Not Designated as Hedging Instrument \| RPAs sold
Derivative Asset [Abstract]
Notional Amount	0	0
Fair Value	0	0
Derivative Liability [Abstract]
Notional Amount	854	899
Fair Value	2	3
Not Designated as Hedging Instrument \| RPAs purchased
Derivative Asset [Abstract]
Notional Amount	35,305	14,710
Fair Value	71	21
Derivative Liability [Abstract]
Notional Amount	0	0
Fair Value	$ 0	$ 0

Nominal or face amount used to calculate payments on the derivative asset.

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-Publisher FASB
-Name Accounting Standards Codification
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Fair value, after offset of derivative liability, of financial asset or other 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, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, after offset of derivative asset, of 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, elected not to be and before offset against a right to receive collateral under a master netting arrangement. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

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Amount of right to receive cash collateral under master netting arrangements offset against derivative liabilities.

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Nominal or face amount used to calculate payments on the derivative liability.

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