Equity and Accumulated Other Comprehensive Loss, Net (Summary of Activity for Noncontrolling Interests in the Operating Partnership) (Details) - shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Noncontrolling Interest, Shares [Roll Forward]
Balance as of Beginning of Period (in shares)	2,475,663	2,833,326	3,013,661
New issues of stock during period (in shares/units)	6,111,770
Redemption of common units for shares of Digital Realty Trust, Inc. common stock (in shares)	(354,490)	(279,500)	(42,500)
Conversion of incentive units held by employees and directors for shares of Digital Realty Trust, Inc. common stock (in shares)	(208,092)	(150,993)	(113,508)
Cancellation of incentive units held by employees and directors (in shares)		(74,246)	(151,579)
Incentive units issued upon achievement of market performance condition (in shares)	390,795		127,252
Grant of incentive units to employees and directors (in share)	(73,449)	(1,416)
Balance as of End of Period (in shares)	8,489,095	2,475,663	2,833,326
Common Units
Noncontrolling Interest, Shares [Roll Forward]
Balance as of Beginning of Period (in shares)	1,141,814	1,421,314	1,463,814
New issues of stock during period (in shares/units)	6,111,770
Redemption of common units for shares of Digital Realty Trust, Inc. common stock (in shares)	(354,490)	(279,500)	(42,500)
Conversion of incentive units held by employees and directors for shares of Digital Realty Trust, Inc. common stock (in shares)	0	0	0
Cancellation of incentive units held by employees and directors (in shares)			0
Incentive units issued upon achievement of market performance condition (in shares)	0		0
Grant of incentive units to employees and directors (in share)	0
Balance as of End of Period (in shares)	6,899,094	1,141,814	1,421,314
Incentive Units
Noncontrolling Interest, Shares [Roll Forward]
Balance as of Beginning of Period (in shares)	1,333,849	1,412,012	1,549,847
New issues of stock during period (in shares/units)	0
Redemption of common units for shares of Digital Realty Trust, Inc. common stock (in shares)	0	0	0
Conversion of incentive units held by employees and directors for shares of Digital Realty Trust, Inc. common stock (in shares)	(208,092)	(150,993)	(113,508)
Cancellation of incentive units held by employees and directors (in shares)		(74,246)	(151,579)
Incentive units issued upon achievement of market performance condition (in shares)	390,795		127,252
Grant of incentive units to employees and directors (in share)	(73,449)	(1,416)
Balance as of End of Period (in shares)	1,590,001	1,333,849	1,412,012