Valuation and Qualifying Accounts - Schedule of Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Allowance For Doubtful Accounts [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	$ 460	$ 680	$ 713
Charged to (Recovery of) Costs and Expense	293	(222)	5
Deductions	62	(2)	38
Balance at End of Period	691	460	680
Deferred Tax Valuation Allowance [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	2,447	1,924	2,205
Charged to (Recovery of) Costs and Expense	725	626	71
Charged to Other Accounts (net)		(103)	(352)
Balance at End of Period	$ 3,172	$ 2,447	$ 1,924