Line of Credit (Details) $ in Thousands	1 Months Ended	12 Months Ended
	May 31, 2015 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2015 USD ($)
Line Of Credit Facility [Line Items]
Revolving line of credit, maximum borrowing capacity		$ 20,000
Quick ratio		1.25
Amount drawn from revolving line of credit			$ 3,300
Repayments of revolving line of credit			$ 7,600
Line of Credit Facility, Remaining Borrowing Capacity				$ 18,500
Prime Rate
Line Of Credit Facility [Line Items]
Revolving line of credit, basis spread over variable rate		5.00%
Letter of Credit [Member]
Line Of Credit Facility [Line Items]
Revolving line of credit amount outstanding		$ 0		$ 0
Amount drawn from revolving line of credit	$ 1,500