Summary of Significant Accounting Policies - Reconciliation of Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance as of beginning of period	$ 1,028
Provisions to allowance for doubtful accounts	1,068	$ 1,001
Write-offs	(290)
Balance as of end of period	$ 1,806	$ 1,028