Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Summary of Significant Accounting Policies [Abstract]
Beginning balance	$ 31	$ 389
Charges to costs and expenses	(24)	(235)
Accounts charged off, less recoveries		(123)
Ending balance	$ 7	$ 31