Commitments and Contingencies (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Commitments and Contingencies Disclosure [Line Items]
Operating leases rental expense	$ 1,100	$ 1,100	$ 3,200	$ 3,300
Minimum [Member]
Commitments and Contingencies Disclosure [Line Items]
Lease expiration period			8 months
Lease expiration period, renewal option			1 year
Maximum [Member]
Commitments and Contingencies Disclosure [Line Items]
Lease expiration period			22 years
Lease expiration period, renewal option			5 years
Commitments to extend credit on standby letters of credit [Member] | Commitments to extend credit [Member]
Commitments and Contingencies Disclosure [Line Items]
Contract amount	$ 7,993		$ 7,993		$ 6,666