Summary of Significant Accounting Policies - Revision of Previously Issued Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Accounts payable and accrued expenses	$ 12,591	$ 12,845
Income tax liabilities	8,424	9,778
Total Liabilities	192,093	234,544
Accumulated deficit	(298,288)	(364,236)
Total Stockholders' Equity	$ 650,329	794,917	$ 1,157,390	$ 1,368,378
As Reported
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Accounts payable and accrued expenses		11,361
Income tax liabilities		0
Total Liabilities		223,282
Accumulated deficit		(352,974)
Total Stockholders' Equity		806,179
2015 Insurance Reserve | Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Accounts payable and accrued expenses		1,484
Income tax liabilities		9,778
Total Liabilities		11,262
Accumulated deficit		(11,262)
Total Stockholders' Equity		$ (11,262)