Equity and Accumulated Other Comprehensive Loss, Net (Noncontrolling Interests in Operating Partnership) (Details) $ in Millions	Dec. 31, 2018 USD ($) shares	Dec. 31, 2017 USD ($) shares
Class of Stock [Line Items]
Partners' capital account units (in units)	206,425,656	205,470,300
Percentage of total	95.10%	96.00%
Common stock conversion ratio	1
Common units held by third parties
Class of Stock [Line Items]
Common units held by third parties (in units)	6,297,272	6,899,094
Percentage of total	2.90%	3.20%
Incentive units held by employees and directors (see note 14)
Class of Stock [Line Items]
Incentive units held by employees and directors (in units)	1,944,738	1,590,001
Percentage of total	0.90%	0.80%
Noncontrolling Interests in Operating Partnership
Class of Stock [Line Items]
Partners' capital account units (in units)	217,006,540	213,959,395
Percentage of total	99.97967%	100.00%
Ascenty Acquisition
Class of Stock [Line Items]
Issuance of units in connection with Ascenty Acquisition	2,338,874	0
Percentage of total	1.10%	0.00%
Digital Realty Trust, L.P.
Class of Stock [Line Items]
Common stock conversion ratio	1
Redemption value | $	$ 1,076.9	$ 887.0