Summary of Significant Accounting Policies - Revenue and Deferred Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Accounting Policies [Abstract]
Deferred rent receivables	$ 78,900		$ 78,900		$ 63,600
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Aggregate allowance for doubtful accounts	4,600	$ 5,400	4,600	$ 5,400
Deferred income	114,978	85,400	114,978	85,400	$ 85,351
Amortization of deferred revenue	7,200	4,500	13,700	8,400
Company recorded equity-based compensation expense net of repurchased awards and forfeits	$ 7,300	$ 6,100	$ 14,200	$ 11,000
Cloud and managed services | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining term	3 years		3 years