Derivative Instruments and Hedging Activities (Details) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($) Agreement	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Interest rate derivatives - Included Component [Abstract]
Amount of Gain or (Loss) Recognized in OCI	$ 1,218	$ 901	$ 2,832
Amount of Gain or (Loss) Reclassified from AOCI into interest (income) expense	(2,300)	(292)	69
Derivatives Designated as Hedging Instruments [Member] \| Interest Rate Derivatives [Member]
Fair value adjustment recorded related to notional amount of derivatives outstanding and notional amount of risk participation agreements [Abstract]
Fair value adjustment	2,428	3,510
Notional amount	225,000	250,000
Derivatives Designated as Hedging Instruments [Member] \| Cash Flow Hedging [Member]
Interest rate derivatives - Included Component [Abstract]
Amount of Gain or (Loss) Recognized in OCI	1,218	901	2,832
Derivatives Designated as Hedging Instruments [Member] \| Cash Flow Hedging [Member] \| Interest (Income) Expense [Member]
Interest rate derivatives - Included Component [Abstract]
Amount of Gain or (Loss) Reclassified from AOCI into interest (income) expense	(2,300)	(292)	69
Derivatives Designated as Hedging Instruments [Member] \| Cash Flow Hedging [Member] \| Interest Rate Derivatives [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	(2,300)
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	$ (120)	101	$ 0
Derivatives Not Designated as Hedging Instruments [Member] \| Interest Rate Derivatives [Member]
Interest rate derivatives [Abstract]
Number of risk participation agreements held \| Agreement	9
Fair value adjustment recorded related to notional amount of derivatives outstanding and notional amount of risk participation agreements [Abstract]
Fair value adjustment	$ 17,572	210
Notional amount	653,369	481,185
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	$ 70,785	$ 35,628

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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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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