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Derivative Instruments and Hedging Activities (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019 USD ($) Agreement	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) Agreement	Jun. 30, 2018 USD ($)	Dec. 31, 2018 USD ($) Agreement
Interest rate derivatives - Included Component [Abstract]
Amount of (loss) or gain recognized in OCI	$ (314)	$ 424	$ (484)	$ 1,472
Amount of (gain) reclassified from AOCI into interest expense	(738)	(540)	(1,537)	(899)
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	521		521		$ 2,428
Fair value adjustment included in other liabilities	18		18		0
Notional amount	150,000		150,000		$ 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	(314)	424	(484)	1,472
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	(738)	(540)	(1,537)	(899)
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			500
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 in other income	$ 19	$ 320	$ 106	$ 123
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	$ 38,454		$ 38,454		$ 17,572
Notional amount	757,614		757,614		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	69		69		36
Derivatives Not Designated as Hedging Instruments [Member] \| Interest Rate Swaps [Member] \| Other Liabilities [Member]
Interest rate derivatives [Abstract]
Fair value of derivative liability	93		93		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	$ 73,141		$ 73,141		$ 70,785