Description of the Business And Summary of Significant Accounting Policies - Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Allowance for Doubtful Accounts Receivable [Roll Forward]
Allowance for Accounts Receivables, Beginning Balance	$ 1,462	$ 1,972	$ 113
Charge-offs	(136)	(1,161)	(431)
Provision (benefit) for bad debts	(441)	651	2,290
Allowance for Accounts Receivables, Ending Balance	$ 885	$ 1,462	$ 1,972