Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Period Type:	instant

Summary of Significant Accounting Policies - Foreign Currency Transactions (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Mar. 31, 2018	Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total stockholders’ equity	$ 561,895			$ 352,850
Retained earnings (accumulated deficit)	(1,174,978)		$ 383	$ (1,063,610)
Net cash used in operating activities	$ (106,516)	$ (91,757)
Accumulated Foreign Currency Adjustment Attributable
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total stockholders’ equity			$ (383)
Accounting Standards Update 2016-18
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net cash used in operating activities		$ 6