Equity and Accumulated Other Comprehensive Loss, Net (Noncontrolling Interests in Operating Partnership) (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Class of Stock [Line Items]
Number of units (units)	279,920,621	208,900,758
Percentage of total	97.20%	95.90%
Common stock conversion ratio	1
Digital Realty Trust, L.P.
Class of Stock [Line Items]
Redeemable noncontrolling interests - operating partnership	$ 1,154.9	$ 997.6
Common units held by third parties
Class of Stock [Line Items]
Common units held by third parties (units)	6,291,091	6,820,201
Percentage of total	2.20%	3.20%
Incentive units held by employees and directors (see Note 14)
Class of Stock [Line Items]
Incentive units held by employees and directors (units)	1,875,570	2,022,954
Percentage of total	0.60%	0.90%
Noncontrolling Interests in Operating Partnership
Class of Stock [Line Items]
Number of units (units)	288,087,282	217,743,913
Percentage of total	100.00%	100.00%