Segment and Geographic Information (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2017 USD ($) segment	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Revenues from External Customers and Long-Lived Assets [Line Items]
Number of operating segments | segment									1
Total net revenues	$ 8,595	$ 7,868	$ 10,861	$ 17,465	$ 17,429	$ 31,084	$ 48,573	$ 46,075	$ 44,789	$ 143,161	$ 294,547
Long-lived assets	309,679				703,164				309,679	703,164
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total net revenues									$ 37,131	$ 131,572	$ 275,118
Percentage of revenue by geographic segments									82.90%	91.90%	93.40%
Long-lived assets	$ 308,843				$ 699,004				$ 308,843	$ 699,004
Percentage of long-lived assets by geographic segments	99.70%				99.40%				99.70%	99.40%
Europe [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total net revenues									$ 7,239	$ 9,331	$ 16,745
Percentage of revenue by geographic segments									16.20%	6.50%	5.70%
Long-lived assets	$ 836				$ 4,160				$ 836	$ 4,160
Percentage of long-lived assets by geographic segments	0.30%				0.60%				0.30%	0.60%
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total net revenues									$ 419	$ 2,258	$ 2,684
Percentage of revenue by geographic segments									0.90%	1.60%	0.90%