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Derivative Instruments and Hedging Activities (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019 USD ($) Agreement	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) Agreement	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($) Agreement
Interest rate derivatives - Included Component [Abstract]
Amount of (loss) or gain recognized in OCI	$ 9	$ 175	$ (475)	$ 1,647
Amount of (gain) reclassified from AOCI into interest expense	(395)	(638)	(1,932)	(1,537)
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 included in other assets	142		142		$ 2,428
Fair value adjustment included in other liabilities	61		61		0
Notional amount	100,000		100,000		$ 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	9	175	(475)	1,647
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	(395)	(638)	(1,932)	(1,537)
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			100
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]
(Decrease) increase in other income	$ (10)	$ (13)	$ 96	$ 110
Derivatives Not Designated as Hedging Instruments [Member] \| Interest Rate Swaps [Member]
Interest rate derivatives [Abstract]
Number of risk participation agreements held \| Agreement	10		10		9
Fair value adjustment recorded related to notional amount of derivatives outstanding and notional amount of risk participation agreements [Abstract]
Fair value adjustment included in other assets and other liabilities	$ 52,925		$ 52,925		$ 17,572
Notional amount	793,805		793,805		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	81		81		36
Derivatives Not Designated as Hedging Instruments [Member] \| Interest Rate Swaps [Member] \| Other Liabilities [Member]
Interest rate derivatives [Abstract]
Fair value of derivative liability	116		116		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	$ 72,496		$ 72,496		$ 70,785