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

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Equity-Based Compensation (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	May 31, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated stock-based compensation expense		$ 5,863	$ 8,832	$ 17,376	$ 26,176
Unrecognized compensation expense, stock options		4,300		4,300
Senior Managing Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options forfeited (in shares)	98,603
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated stock-based compensation expense		1,454	2,070	$ 3,146	6,264
Period for recognition				9 months 18 days
Employee Stock Option \| Employee equity grant expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated stock-based compensation expense		221	14	$ 573	71
Stock Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated stock-based compensation expense		1,775	2,089	4,088	6,950
Stock Compensation Plan \| Director and other non-employee equity grants expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated stock-based compensation expense		100	5	369	615
Stock Compensation Plan \| REIT equity-based compensation
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated stock-based compensation expense		4,088	$ 6,743	13,288	$ 19,226
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense, stock options		$ 2,100		$ 2,100
Period for recognition				2 years 3 months 18 days