Real Estate Assets and Construction in Progress (Summary of Owned or Leased Properties by the Company) (Details) $ in Thousands	Mar. 31, 2020 USD ($) facility	Dec. 31, 2019 USD ($) facility
Real Estate Properties [Line Items]
Land	$ 130,576	$ 130,605
Buildings, Improvements and Equipment	2,411,426	2,178,901
Construction in progress	877,313	920,922
Owned Properties
Real Estate Properties [Line Items]
Land	130,576	130,605
Buildings, Improvements and Equipment	2,411,426	2,178,901
Construction in progress	877,313	920,922
Total cost	3,419,315	3,230,428
Owned Properties | Atlanta, Georgia Campus
Real Estate Properties [Line Items]
Land	44,588	44,588
Buildings, Improvements and Equipment	561,369	525,300
Construction in progress	148,660	128,930
Total cost	754,617	698,818
Owned Properties | Irving, Texas
Real Estate Properties [Line Items]
Land	8,605	8,606
Buildings, Improvements and Equipment	370,483	369,727
Construction in progress	107,072	98,170
Total cost	486,160	476,503
Owned Properties | Ashburn, Virginia
Real Estate Properties [Line Items]
Land	16,476	16,476
Buildings, Improvements and Equipment	301,886	156,396
Construction in progress	89,564	189,375
Total cost	407,926	362,247
Owned Properties | Richmond, Virginia
Real Estate Properties [Line Items]
Land	2,180	2,180
Buildings, Improvements and Equipment	196,766	195,684
Construction in progress	140,855	139,948
Total cost	339,801	337,812
Owned Properties | Chicago, Illinois
Real Estate Properties [Line Items]
Land	9,400	9,400
Buildings, Improvements and Equipment	205,698	205,026
Construction in progress	98,001	86,878
Total cost	313,099	301,304
Owned Properties | Suwanee, Georgia (Atlanta-Suwanee)
Real Estate Properties [Line Items]
Land	3,521	3,521
Buildings, Improvements and Equipment	174,594	174,124
Construction in progress	5,302	5,559
Total cost	183,417	183,204
Owned Properties | Piscataway New Jersey
Real Estate Properties [Line Items]
Land	7,466	7,466
Buildings, Improvements and Equipment	105,784	103,553
Construction in progress	38,791	36,056
Total cost	152,041	147,075
Owned Properties | Santa Clara, California
Real Estate Properties [Line Items]
Buildings, Improvements and Equipment	116,282	114,499
Construction in progress	185	1,238
Total cost	116,467	115,737
Owned Properties | Fort Worth, Texas
Real Estate Properties [Line Items]
Land	9,079	9,079
Buildings, Improvements and Equipment	98,224	55,018
Construction in progress	3,415	35,722
Total cost	110,718	99,819
Owned Properties | Hillsboro, Oregon
Real Estate Properties [Line Items]
Construction in progress	96,728	63,573
Total cost	96,728	63,573
Owned Properties | Sacramento, California
Real Estate Properties [Line Items]
Land	1,481	1,481
Buildings, Improvements and Equipment	65,373	65,258
Construction in progress	263	163
Total cost	67,117	66,902
Owned Properties | Dulles, Virginia
Real Estate Properties [Line Items]
Land	3,154	3,154
Buildings, Improvements and Equipment	50,159	48,651
Construction in progress	5,799	4,688
Total cost	59,112	56,493
Owned Properties | Manassas, Virginia
Real Estate Properties [Line Items]
Buildings, Improvements and Equipment	13
Construction in progress	58,909	57,662
Total cost	58,922	57,662
Owned Properties | Princeton, New Jersey
Real Estate Properties [Line Items]
Land	20,700	20,700
Buildings, Improvements and Equipment	35,220	35,192
Construction in progress	9	39
Total cost	55,929	55,931
Owned Properties | Eemshaven, Netherlands
Real Estate Properties [Line Items]
Construction in progress	46,450	37,267
Total cost	46,450	37,267
Owned Properties | Phoenix, Arizona
Real Estate Properties [Line Items]
Buildings, Improvements and Equipment		2,412
Construction in progress	33,252	31,840
Total cost	33,252	34,252
Owned Properties | Groningen, Netherlands
Real Estate Properties [Line Items]
Land	1,713	1,741
Buildings, Improvements and Equipment	9,311	9,085
Construction in progress	3,089	3,028
Total cost	14,113	13,854
Owned Properties | Other
Real Estate Properties [Line Items]
Land	2,213	2,213
Buildings, Improvements and Equipment	36,066	36,163
Construction in progress	498	120
Total cost	38,777	38,496
Leased Properties
Real Estate Properties [Line Items]
Buildings, Improvements and Equipment	84,198	82,813
Construction in progress	471	666
Total cost	$ 84,669	$ 83,479
Number of facilities leased | facility	7	7