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Exercise price per share or per unit of warrants or rights outstanding.

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Number of warrants or rights outstanding.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands					1 Months Ended	3 Months Ended	9 Months Ended
	Aug. 25, 2020	Mar. 10, 2020	Jan. 28, 2020	May 01, 2019	Jun. 30, 2020	Sep. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Private placement, loss recorded in additional paid-in-capital						$ 444	$ 444
Purchase of treasury stock (in shares)		800,000	1,000,000.0	24,000,000.0	800,000
Purchase of treasury stock		$ 9,200	$ 12,600	$ 438,000	$ 8,800		$ 30,626	$ 437,962
Payments for stock options exercised				$ 33,900
Warrants outstanding (in shares)						10,500,000	10,500,000		10,500,000
Number of shares of common stock to be issued for upon exercise of warrants (in shares)						5,800,000	5,800,000	5,800,000
Warrant, exercise price (in usd per share)						$ 24.39	$ 24.39	$ 24.39
Additional Paid-in Capital
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Private placement, loss recorded in additional paid-in-capital	$ (800)					$ (813)	$ (813)
Private Placement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued (in shares)	68,857
Price per share (in usd per share)	$ 10.17
Total value raised, net of expenses	$ 400
Affiliated Entity
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options settled in period (in shares)				2,300,000
Affiliated Entity \| Mudrick Capital Management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase of treasury stock (in shares)				11,100,000
Purchase of treasury stock				$ 202,600
Affiliated Entity \| Paulson and Co
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase of treasury stock (in shares)				5,600,000
Purchase of treasury stock				$ 102,200
Affiliated Entity \| GoldenTree Asset Management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase of treasury stock (in shares)				4,200,000
Purchase of treasury stock				$ 75,800