Organization and Nature of Business - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) segment	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Number of reportable segments | segment	1
Net loss	$ (2,343,309)	$ (694,426)	$ (510,763)
Stockholders' deficit due to impairment of Angola assets	(841,334)	$ 1,446,137	$ 2,114,266	$ 2,129,146
Compensating cash balance	$ 200,000