Derivatives and Hedging Activities (Summary of Derivative Positions) (Details)	12 Months Ended
	Dec. 31, 2019 USD ($) derivative	Dec. 31, 2018 USD ($) derivative
Loss Recognized in Income on Derivatives
Gain (loss) recognized in income	$ 679,000	$ 206,000
Estimated net credit risk exposure	0	0
Collateral posted	86,500,000	5,900,000
Receive fixed, pay variable
Derivatives and Hedging Activities
Total	$ 1,101,193,000	$ 714,500,000
Receive fixed, pay variable | Derivatives not designed as hedging instruments
Derivatives and Hedging Activities
Number of Positions | derivative	119,000	86,000
Notional Amount Maturing, Less than 1 year	$ 24,777,000	$ 1,931,000
Notional Amount Maturing, Less than 2 years	0	26,419,000
Notional Amount Maturing, Less than 3 years	31,131,000	0
Notional Amount Maturing, Less than 4 years	16,794,000	31,762,000
Notional Amount Maturing, Thereafter	1,028,491,000	654,388,000
Total	1,101,193,000	714,500,000
Fair Value	58,102,000	6,081,000
Pay fixed, receive variable
Derivatives and Hedging Activities
Total	$ 1,101,193,000	$ 714,500,000
Pay fixed, receive variable | Derivatives not designed as hedging instruments
Derivatives and Hedging Activities
Number of Positions | derivative	119,000	86,000
Notional Amount Maturing, Less than 1 year	$ 24,777,000	$ 1,931,000
Notional Amount Maturing, Less than 2 years	0	26,419,000
Notional Amount Maturing, Less than 3 years	31,131,000	0
Notional Amount Maturing, Less than 4 years	16,794,000	31,762,000
Notional Amount Maturing, Thereafter	1,028,491,000	654,388,000
Total	1,101,193,000	714,500,000
Fair Value	58,102,000	6,081,000
Risk participation-out agreements
Derivatives and Hedging Activities
Total	235,693,000	100,531,000
Loss Recognized in Income on Derivatives
Gain (loss) recognized in income	$ 686,000	$ 205,000
Risk participation-out agreements | Derivatives not designed as hedging instruments
Derivatives and Hedging Activities
Number of Positions | derivative	40,000	26,000
Notional Amount Maturing, Less than 1 year	$ 13,967,000	$ 0
Notional Amount Maturing, Less than 2 years	0	14,892,000
Notional Amount Maturing, Less than 3 years	0	0
Notional Amount Maturing, Less than 4 years	7,143,000	0
Notional Amount Maturing, Thereafter	214,583,000	85,639,000
Total	235,693,000	100,531,000
Fair Value	1,229,000	344,000
Risk participation-in agreements
Derivatives and Hedging Activities
Total	$ 55,281,000	$ 35,838,000
Risk participation-in agreements | Derivatives not designed as hedging instruments
Derivatives and Hedging Activities
Number of Positions | derivative	7,000	5,000
Notional Amount Maturing, Less than 1 year	$ 0	$ 0
Notional Amount Maturing, Less than 2 years	0	0
Notional Amount Maturing, Less than 3 years	0	0
Notional Amount Maturing, Less than 4 years	19,000,000	0
Notional Amount Maturing, Thereafter	36,281,000	35,838,000
Total	55,281,000	35,838,000
Fair Value	283,000	84,000
Foreign exchange contracts
Loss Recognized in Income on Derivatives
Gain (loss) recognized in income	(7,000)	1,000
Buys foreign currency, sells U.S. currency | Foreign exchange contracts
Derivatives and Hedging Activities
Total	$ 1,125,000	$ 6,573,000
Buys foreign currency, sells U.S. currency | Foreign exchange contracts | Derivatives not designed as hedging instruments
Derivatives and Hedging Activities
Number of Positions | derivative	16,000	22,000
Notional Amount Maturing, Less than 1 year	$ 1,125,000	$ 6,573,000
Notional Amount Maturing, Less than 2 years	0	0
Notional Amount Maturing, Less than 3 years	0	0
Notional Amount Maturing, Less than 4 years	0	0
Notional Amount Maturing, Thereafter	0	0
Total	1,125,000	6,573,000
Fair Value	54,000	123,000
Sells foreign currency, buys U.S. currency | Foreign exchange contracts
Derivatives and Hedging Activities
Total	$ 1,230,000	$ 6,582,000
Sells foreign currency, buys U.S. currency | Foreign exchange contracts | Derivatives not designed as hedging instruments
Derivatives and Hedging Activities
Number of Positions | derivative	18,000	37,000
Notional Amount Maturing, Less than 1 year	$ 1,230,000	$ 6,582,000
Notional Amount Maturing, Less than 2 years	0	0
Notional Amount Maturing, Less than 3 years	0	0
Notional Amount Maturing, Less than 4 years	0	0
Notional Amount Maturing, Thereafter	0	0
Total	1,230,000	6,582,000
Fair Value	$ 53,000	$ 131,000