Summary of Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended			17 Months Ended
	Dec. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2015	Jul. 23, 2014
Summary Of Significant Accounting Policies [Line Items]
Useful life of property		40 years
Depreciation expense from operation		$ 65,000	$ 45,400	$ 36,700
Real estate cost capitalized excluding interest cost		10,800	10,600	8,500
Real estate interest cost capitalized incurred		9,800	6,500	4,100
Amortization of below market lease		100	0	0
Amortization of the deferred financing costs	$ 496	3,181	2,673
Deferred leasing costs, net		16,434	16,469		$ 16,434
In Place Leases [Member]
Summary Of Significant Accounting Policies [Line Items]
Amortization of lease costs		1,700	2,200	2,600
Tenant Relationship [Member]
Summary Of Significant Accounting Policies [Line Items]
Amoritzation of intangible assets		5,000	1,300	1,500
Platform [Member]
Summary Of Significant Accounting Policies [Line Items]
Amoritzation of intangible assets		1,700	0	0
Trade Names [Member]
Summary Of Significant Accounting Policies [Line Items]
Amoritzation of intangible assets		600	0	0
Qualitytech, LP [Member]
Summary Of Significant Accounting Policies [Line Items]
Amortization of the deferred financing costs		3,181	2,673	2,777
Real Estate Assets [Member]
Summary Of Significant Accounting Policies [Line Items]
Depreciation expense from operation		55,200	39,000	31,500
Non-Real Estate Assets [Member]
Summary Of Significant Accounting Policies [Line Items]
Depreciation expense from operation		$ 9,800	6,400	$ 5,200
Minimum [Member] | Real Property [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful life of property		20 years
Maximum [Member] | Real Property [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful life of property		40 years
Maximum [Member] | Leasehold Improvements [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful life of property		20 years
Senior Notes [Member]
Summary Of Significant Accounting Policies [Line Items]
Interest rate		5.875%			5.875%	5.875%
Senior notes due		2022			2022
Princeton Facility [Member]
Summary Of Significant Accounting Policies [Line Items]
Deferred leasing costs, net			$ 2,800