Schedule II - Valuation and Qualifying Accounts - Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
SEC Schedule, 12-09, Allowance, Credit Loss [Member]
Balance at Beginning of Period	$ 477	$ 515	$ 751	[1]
Charged to Profit and Loss	449	637	295
Deduction from Reserves	(266)	(675)	(531)
Balance at End of Period	660	477	515
SEC Schedule, 12-09, Valuation Allowance, Deferred Tax Asset [Member]
Balance at Beginning of Period	10,413	8,217	7,057
Charged to Profit and Loss	1,785	2,196	1,160
Deduction from Reserves	(2,765)
Balance at End of Period	$ 9,433	$ 10,413	$ 8,217

[1] Includes amounts that were classified as held for sale.