Summary of Significant Accounting Policies (Additional Information 1) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Summary Of Significant Accounting Policies [Line Items]
Assets held for sale					$ 71,800
Liabilities held for sale					24,349
Amortization of the deferred financing costs	$ 1,000	$ 1,000	$ 2,935	$ 2,882
Amortization of deferred leasing costs	6,700	5,500	17,700	15,700
Aggregate allowance for doubtful accounts	1,900		1,900		3,800
Deferred income	41,404		41,404		33,241
Amortization of deferred revenue	4,000	3,300	11,100	9,400
Company recorded equity-based compensation expense net of repurchased awards and forfeits	4,500	$ 3,900	$ 12,100	11,400
Equity based compensation associated with the acceleration of equity awards				$ 3,100
Practical Expedient, remaining term			true
Amount of the straight-line rent receivable on the balance sheets included in rents and other receivables, net	$ 34,600		$ 34,600		$ 29,700
Cloud and managed services | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-01-01
Summary Of Significant Accounting Policies [Line Items]
Remaining term	3 years		3 years