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

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Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Derivative Instruments and Hedging Activities (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($) Agreement	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($) Agreement
Interest rate derivatives - Included Component [Abstract]
Amount of (loss) or gain recognized in OCI	$ (170)	$ 1,048
Amount of (gain) reclassified from AOCI into interest expense	(799)	(359)
Derivatives Designated as Hedging Instruments [Member] \| Interest Rate Swaps [Member]
Fair value adjustment recorded related to notional amount of derivatives outstanding and notional amount of risk participation agreements [Abstract]
Fair value adjustment	1,595		$ 2,428
Notional amount	200,000		$ 225,000
Derivatives Designated as Hedging Instruments [Member] \| Cash Flow Hedging [Member]
Interest rate derivatives - Included Component [Abstract]
Amount of (loss) or gain recognized in OCI	(170)	1,048
Derivatives Designated as Hedging Instruments [Member] \| Cash Flow Hedging [Member] \| Interest (Income) Expense [Member]
Interest rate derivatives - Included Component [Abstract]
Amount of (gain) reclassified from AOCI into interest expense	(799)	(359)
Derivatives Designated as Hedging Instruments [Member] \| Cash Flow Hedging [Member] \| Interest Rate Swaps [Member]
Fair value adjustment recorded related to notional amount of derivatives outstanding and notional amount of risk participation agreements [Abstract]
Amount to be reclassified from AOCI as a reduction to interest expense during next twelve months	1,400
Derivatives Not Designated as Hedging Instruments [Member] \| Other Income [Member]
Gain or loss recognized in income on derivatives not designating as a hedging relationship [Abstract]
(Increase) decrease in other income	$ (87)	$ 197
Derivatives Not Designated as Hedging Instruments [Member] \| Interest Rate Swaps [Member]
Interest rate derivatives [Abstract]
Number of risk participation agreements held \| Agreement	10		9
Fair value adjustment recorded related to notional amount of derivatives outstanding and notional amount of risk participation agreements [Abstract]
Fair value adjustment	$ 22,231		$ 17,572
Notional amount	695,522		653,369
Derivatives Not Designated as Hedging Instruments [Member] \| Interest Rate Swaps [Member] \| Other Assets [Member]
Interest rate derivatives [Abstract]
Fair value of derivative asset	45		36
Derivatives Not Designated as Hedging Instruments [Member] \| Interest Rate Swaps [Member] \| Other Liabilities [Member]
Interest rate derivatives [Abstract]
Fair value of derivative liability	35		17
Derivatives Not Designated as Hedging Instruments [Member] \| Risk Participation Agreements [Member]
Fair value adjustment recorded related to notional amount of derivatives outstanding and notional amount of risk participation agreements [Abstract]
Notional amount	$ 77,771		$ 70,785