Summary of Significant Accounting Policies - Trade Receivables (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Allowance for Doubtful Accounts Receivable [Roll Forward]
Allowance for doubtful accounts, beginning balance	$ 4,371	$ 1,949	$ 1,490
Charged to costs and expenses	1,886	3,767	1,407
Amounts charged off, net	(2,711)	(1,345)	(948)
Allowance for doubtful accounts, ending balance	$ 3,546	$ 4,371	$ 1,949