Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Stock-Based Compensation - Performance-based Awards (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended										9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2021	Sep. 30, 2020
Fair Market Value
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Valuation Method		Fair Market Value	Fair Market Value	Fair Market Value	Fair Market Value	Fair Market Value	Fair Market Value		Fair Market Value
Black-Scholes Merton
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Valuation Method		Black-Scholes-Merton			Black-Scholes-Merton		Black-Scholes-Merton
Monte-Carlo
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Valuation Method		Monte-Carlo Simulation	Monte-Carlo Simulation	Monte-Carlo Simulation			Monte-Carlo Simulation	Monte-Carlo Simulation		Monte-Carlo Simulation
Performance-based awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 9,600				$ 6,600						$ 39,500	$ 11,800
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs Granted (in shares)											1,528
Vested (in shares)											1,707
Restricted stock units \| Fair Market Value
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs Granted (in shares)		7	279	22	27	21	436		188
Vested (in shares)			10	2	17	21	406		81
Restricted stock units \| Monte-Carlo
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs Granted (in shares)			125	32			300	50		300
Vested (in shares)				6			225	50		300
Employee and non-employee stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)											391
RSUs Granted (in shares)											1,528
Stock-based compensation expense	$ 26,459				$ 15,032						$ 84,797	$ 34,406
Employee and non-employee stock options \| Black-Scholes Merton
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)		29			10		129
Options Vested (in shares)					10		129
Employee and non-employee stock options \| Monte-Carlo
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)		163	150				150			200
Options Vested (in shares)							113			201