Real Estate Assets and Construction in Progress (Summary of Properties Owned or Leased by the Company) (Details) $ in Thousands		Jun. 30, 2016 USD ($) property	Dec. 31, 2015 USD ($) property
Real Estate Properties [Line Items]
Land		$ 64,568	$ 57,112
Buildings, improvements and equipment		1,393,920	1,180,386
Construction in progress		316,797	345,655
Total cost		1,775,285	1,583,153
Owned Properties [Member]
Real Estate Properties [Line Items]
Land		63,438	55,982
Buildings, improvements and equipment		1,277,611	1,061,247
Construction in progress		308,168	336,034
Total cost		1,649,217	1,453,263
Owned Properties [Member] | Suwanee, Georgia (Atlanta-Suwanee) [Member]
Real Estate Properties [Line Items]
Land		3,521	3,521
Buildings, improvements and equipment		153,392	150,028
Construction in progress		16,040	15,330
Total cost		172,953	168,879
Owned Properties [Member] | Atlanta, Georgia (Atlanta-Metro) [Member]
Real Estate Properties [Line Items]
Land		15,397	15,397
Buildings, improvements and equipment		430,815	406,190
Construction in progress		26,206	41,835
Total cost		472,418	463,422
Owned Properties [Member] | Santa Clara, California [Member]
Real Estate Properties [Line Items]
Land	[1]
Buildings, improvements and equipment	[1]	96,268	94,437
Construction in progress	[1]	2,769	1,379
Total cost	[1]	99,037	95,816
Owned Properties [Member] | Richmond, Virginia [Member]
Real Estate Properties [Line Items]
Land		2,180	2,180
Buildings, improvements and equipment		236,512	208,654
Construction in progress		65,013	85,771
Total cost		303,705	296,605
Owned Properties [Member] | Sacramento, California [Member]
Real Estate Properties [Line Items]
Land		1,481	1,481
Buildings, improvements and equipment		61,718	61,462
Construction in progress		92	73
Total cost		63,291	63,016
Owned Properties [Member] | Princeton, New Jersey [Member]
Real Estate Properties [Line Items]
Land		20,700	20,700
Buildings, improvements and equipment		32,752	32,708
Construction in progress		483	422
Total cost		53,935	53,830
Owned Properties [Member] | Dallas-Fort Worth, Texas [Member]
Real Estate Properties [Line Items]
Land		8,606	8,590
Buildings, improvements and equipment		151,385	71,783
Construction in progress		74,646	120,331
Total cost		234,637	200,704
Owned Properties [Member] | Chicago, Illinois [Member]
Real Estate Properties [Line Items]
Land
Buildings, improvements and equipment		141
Construction in progress		108,172	70,749
Total cost		108,313	70,749
Owned Properties [Member] | Miami, Florida [Member]
Real Estate Properties [Line Items]
Land		1,777	1,777
Buildings, improvements and equipment		30,851	30,554
Construction in progress		276	144
Total cost		32,904	32,475
Owned Properties [Member] | Lenexa, Kansas [Member]
Real Estate Properties [Line Items]
Land		437	437
Buildings, improvements and equipment		3,511	3,511
Construction in progress		22
Total cost		3,970	3,948
Owned Properties [Member] | Deluth, Georgia [Member]
Real Estate Properties [Line Items]
Land		1,899	1,899
Buildings, improvements and equipment		1,896	1,920
Construction in progress		427
Total cost		4,222	3,819
Owned Properties [Member] | Piscataway, New Jersey [Member]
Real Estate Properties [Line Items]
Land		7,440
Buildings, improvements and equipment		78,370
Construction in progress		14,022
Total cost		99,832
Leased Properties [Member]
Real Estate Properties [Line Items]
Land		1,130	1,130
Buildings, improvements and equipment		116,309	119,139
Construction in progress		8,629	9,621
Total cost		126,068	129,890
Leased Properties [Member] | Jersey City, New Jersey [Member]
Real Estate Properties [Line Items]
Land
Buildings, improvements and equipment		22,738	28,228
Construction in progress		2,021	2,421
Total cost		24,759	30,649
Leased Properties [Member] | Overland Park, Kansas [Member]
Real Estate Properties [Line Items]
Land
Buildings, improvements and equipment	[2]	926	922
Construction in progress		23	4
Total cost		949	926
Leased Properties [Member] | Carpathia Properties [Member]
Real Estate Properties [Line Items]
Land	[3]	1,130	1,130
Buildings, improvements and equipment	[3]	92,645	89,989
Construction in progress	[3]	6,585	7,196
Total cost	[3]	$ 100,360	$ 98,315
Number of facilities leased | property		13	13

[1] Owned facility subject to long-term ground sublease.

[2] This does not include the portion of the business that is used for QTS office space or other real estate not used by customers.

[3] Includes 13 facilities. All facilities are leased, including those subject to capital leases.