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Derivative Instruments and Hedging Activities (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) Agreement	Dec. 31, 2019 USD ($) Agreement	Dec. 31, 2018 USD ($)
Interest rate derivatives - Included Component [Abstract]
Amount of (loss) gain recognized in OCI	$ (275)	$ (459)	$ 1,218
Amount of loss (gain) reclassified from AOCI into interest expense	296	(2,012)	(2,300)
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	0	4
Fair value adjustment included in other liabilities	34	45
Notional amount	25,000	50,000
Derivatives Designated as Hedging Instruments [Member] | Cash Flow Hedging [Member]
Interest rate derivatives - Included Component [Abstract]
Amount of (loss) gain recognized in OCI	(275)	(459)	1,218
Derivatives Designated as Hedging Instruments [Member] | Cash Flow Hedging [Member] | Interest (Income) Expense [Member]
Interest rate derivatives - Included Component [Abstract]
Amount of loss (gain) reclassified from AOCI into interest expense	296	(2,012)	(2,300)
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	21
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	$ 1	$ 295	$ (120)
Derivatives Not Designated as Hedging Instruments [Member] | Interest Rate Swaps [Member]
Interest rate derivatives [Abstract]
Number of risk participation agreements held | Agreement	17	15
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	$ 108,487	$ 41,650
Notional amount	2,447,168	963,209
Derivatives Not Designated as Hedging Instruments [Member] | Interest Rate Swaps [Member] | Other Assets [Member]
Interest rate derivatives [Abstract]
Fair value of derivative asset	292	112
Derivatives Not Designated as Hedging Instruments [Member] | Interest Rate Swaps [Member] | Other Liabilities [Member]
Interest rate derivatives [Abstract]
Fair value of derivative liability	125	82
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	$ 112,313	$ 97,614

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