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Number of options outstanding, including both vested and non-vested options.

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Share-Based Compensation - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021	Aug. 03, 2018	Dec. 03, 2010
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Options outstanding to purchase shares of common stock (in shares)	22,403,822		22,403,822		21,843,781
Share-based payments expense	$ 2,200,000	$ 15,200,000	$ 7,400,000	$ 19,200,000
Unrecognized compensation expense related to non-vested share options	$ 5,800,000		$ 5,800,000
Weighted average period for recognition related to non-vested stock options (in years)			1 year 1 month 28 days
Total intrinsic value of shares exercised			$ 0	5,600,000
Total fair value of vested shares			$ 6,700,000	5,400,000
2010 Stock Incentive Plan ("the Plan")
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of shares authorized for issuance (in shares)						56,800,000	31,500,000
Number of options available for issuance (in shares)	16,700,000		16,700,000
Options
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Options outstanding to purchase shares of common stock (in shares)	22,400,000		22,400,000
Cash received from options exercised			$ 0	$ 8,400,000
Restricted Stock
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized compensation cost related to unvested restricted shares	$ 0		$ 0