Equity and Accumulated Other Comprehensive Loss, Net (Summary of Activity For Noncontrolling Interests in The Operating Partnership) (Details)	9 Months Ended
	Sep. 30, 2018 shares
Common and Incentive Unit Activity [Roll Forward]
As of December 31, 2017 (units)	8,489,095
Redemption of common units for shares of Digital Realty Trust, Inc. common stock (units)	(487,610)
Conversion of incentive units held by employees and directors for shares of Digital Realty Trust, Inc. common stock	(80,182)
Incentive units issued upon achievement of market performance condition	326,947
Grant of incentive units to employees and directors	114,472
Cancellation / forfeitures of incentive units held by employees and directors	(22,135)
As of June 30, 2018 (units)	8,340,587
Common Units
Common and Incentive Unit Activity [Roll Forward]
As of December 31, 2017 (units)	6,899,094
Redemption of common units for shares of Digital Realty Trust, Inc. common stock (units)	(487,610)
Conversion of incentive units held by employees and directors for shares of Digital Realty Trust, Inc. common stock	0
Incentive units issued upon achievement of market performance condition	0
Grant of incentive units to employees and directors	0
Cancellation / forfeitures of incentive units held by employees and directors	0
As of June 30, 2018 (units)	6,411,484
Incentive Units
Common and Incentive Unit Activity [Roll Forward]
As of December 31, 2017 (units)	1,590,001
Redemption of common units for shares of Digital Realty Trust, Inc. common stock (units)	0
Conversion of incentive units held by employees and directors for shares of Digital Realty Trust, Inc. common stock	(80,182)
Incentive units issued upon achievement of market performance condition	326,947
Grant of incentive units to employees and directors	114,472
Cancellation / forfeitures of incentive units held by employees and directors	(22,135)
As of June 30, 2018 (units)	1,929,103