Summary of Significant Accounting Policies - Allowance For Doubtful Accounts Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Allowance for doubtful accounts receivable [Roll Forward]
Beginning balance	$ 3,534	$ 2,723	$ 1,705
Additions	872	1,337	1,610
Deductions (write-offs/recoveries) from reserve	(929)	(531)	(592)
Ending balance	3,477	3,534	2,723
Allowance, net of FX [Member]
Allowance for doubtful accounts receivable [Roll Forward]
Additions	$ 872	$ 1,342	$ 1,610