Summary of Significant Accounting Policies - Rollforward of Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Allowance for Doubtful Accounts
Charged to operating expenses	$ 3,242	$ 1,779	$ 1,217
Continuing Operations
Allowance for Doubtful Accounts
Beginning balance	4,991	4,631	3,703
Charged to operating expenses	3,384	1,627	1,217
Write offs of accounts receivable, net of recoveries	(862)	(1,267)	(289)
Ending balance	$ 7,513	$ 4,991	$ 4,631