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					6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019
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
Black-Scholes Merton
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Valuation Method		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
Performance-based awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 3,800			$ 800		$ 5,200	$ 800
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs Granted (in shares)						2,335
RSUs Vested (in shares)						578
Restricted stock units \| Fair Market Value
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs Granted (in shares)	21	436		188
Restricted stock units \| Monte-Carlo
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs Granted (in shares)		300	50		300
RSUs Vested (in shares)			25		184
Employee and non-employee stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)						446
RSUs Granted (in shares)						4,670
Stock-based compensation expense	$ 11,957			$ 5,804		$ 19,374	$ 9,855
Employee and non-employee stock options \| Black-Scholes Merton
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)		129
Employee and non-employee stock options \| Monte-Carlo
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)		150			200
Options Vested (in shares)					119
Number of options vested					119