Fair Value (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items]
Unrealized loss on derivative, net of tax	$ (1,285)	$ 833
Amounts reclassified from accumulated other comprehensive loss, net of tax	283
Interest Rate Swap [Member]
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items]
Interest rate swap notional amount	$ 150,000		$ 150,000	$ 155,300
Fixed interest rate	2.928%		2.928%	1.4935%
Fair value of interest rate swap	$ 4,400		$ 3,000
Unrealized loss on interest rate swap	1,400
Unrealized loss on derivative, net of tax	1,000
Gain On Contract Termination			$ 3,500
Amounts reclassified from accumulated other comprehensive loss	400
Amounts reclassified from accumulated other comprehensive loss, net of tax	$ 300