Notes Payable (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Jul. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2014
Notes Payable
Interest Expense		$ 159	$ 464
Credit facility
Notes Payable
Proceeds from the issuance of debt				$ 7,000
Term loans balance paid in full	$ 3,500
Penalty for prepayment	$ 0
Interest Expense		$ 200	$ 500