Capital and Accumulated Other Comprehensive Income (Loss) - Forward Equity Sale (Details) - USD ($) $ in Billions	Sep. 24, 2020	Sep. 27, 2018	Dec. 31, 2020	Dec. 31, 2019
Digital Realty Trust, L.P.
Class of Stock
Partnership units issued			8,046,267	8,843,155
Forward Sale Agreement
Class of Stock
Common stock issued in public offering (shares)	9,775,000
Partnership units issued	9,775,000
Forward Sale Agreement | Digital Realty Trust, L.P.
Class of Stock
Common stock issued in public offering (shares)	9,775,000	9,775,000
Net proceeds on public offering	$ 1.0
Over-Allotment Option
Class of Stock
Net proceeds on public offering	$ 1.0
Over-Allotment Option | Digital Realty Trust, L.P.
Class of Stock
Common stock issued in public offering (shares)		1,275,000