Securities (Narrative) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2019 USD ($) security	Jun. 30, 2019 USD ($)	Jan. 01, 2019 USD ($)	Dec. 31, 2018 USD ($) security	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Held to maturity debt securities, at amortized cost	$ 0			$ 10,415
Held to maturity debt securities, fair value	0			10,316
Unrealized losses on held to maturity securities, net of tax	(8,924)	$ (11,866)		(28,309)	$ (39,077)	$ (35,062)	$ (23,510)
Fair value of available for sale and held to maturity securities pledged as collateral	435,300			$ 439,700
Amortized cost of callable debt securities	222,500
Fair value of callable debt securities	$ 220,800
Number of securities in a continuous unrealized loss position total | security	42			90
Unrealized losses of securities in a continuous unrealized loss position total	$ (5,418)			$ (24,396)
Individual name issuer trust preferred debt securities
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Number of securities in a continuous unrealized loss position total | security	5			5
Securities in unrealized loss position, number of companies issuing securities | security	4
Amortized cost of trust preferred securities of individual name issuers that are below investment grade	$ 6,100
Unrealized losses of trust preferred securities of individual name issuers that are below investment grade	458
Unrealized losses of securities in a continuous unrealized loss position total	$ (899)			$ (1,535)
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Number of securities in a continuous unrealized loss position total | security	3			8
Unrealized losses of securities in a continuous unrealized loss position total	$ (1,377)			$ (1,777)
Minimum [Member]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Maturity period of callable debt securities	3 months
Call features of callable debt securities	1 month
Maximum [Member]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Maturity period of callable debt securities	17 years
Call features of callable debt securities	3 years
Adjustments for Change in Accounting Principle [Domain]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Held to maturity debt securities, at amortized cost			$ 10,400
Held to maturity debt securities, fair value			10,300
Unrealized losses on held to maturity securities, net of tax			$ (75)