Summary of Significant Accounting Policies (Additional Information 1) (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Jun. 30, 2016
Summary Of Significant Accounting Policies [Line Items]
Software impairment		$ 1,900
Impairment losses		0	$ 0	$ 0
Goodwill	$ 181,738	173,843	181,738
Amortization of the deferred financing costs		3,285	3,181	2,673
Written off unamortized debt cost	500
Amortization of deferred leasing costs totaled		15,200	11,800	9,400
Deferred income	16,991	21,993	16,991
Amortization of deferred revenue		9,400	6,000	4,700
Deferred leasing costs, net	6,263	6,983	6,263
Company recorded equity-based compensation expense net of repurchased awards and forfeits		10,600	7,000	4,200
Amount of the straight-line rent receivable on the balance sheets included in rents and other receivables, net	$ 9,100	17,300	9,100
Unsecured Revolving Credit Facility [Member]
Summary Of Significant Accounting Policies [Line Items]
Amortization of the deferred financing costs		3,300	$ 3,200	$ 2,700
Written off unamortized debt cost		200
Carpathia Hosting, Inc.
Summary Of Significant Accounting Policies [Line Items]
Goodwill					$ 173,843
Federal cloud product
Summary Of Significant Accounting Policies [Line Items]
Software impairment		1,000
Governance access management software
Summary Of Significant Accounting Policies [Line Items]
Software impairment		$ 900