Capital and Accumulated Other Comprehensive Income (Loss) (Schedule of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Net current period change	$ 28,272	$ (85,300)
Reclassification to interest expense from interest rate swaps	0	0
Cash flow hedge adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Net current period change	5,898	6,246
Reclassification to interest expense from interest rate swaps	2,414	4,890
Accumulated Other Comprehensive Income (Loss), net
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Net current period change	24,759	(43,905)
Reclassification to interest expense from interest rate swaps	2,414	4,890
Digital Realty Trust, L.P.
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance as of Beginning of Period	5,132,297	4,535,137
Balance as of End of Period	11,049,450	5,132,297
Digital Realty Trust, L.P. | Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance as of Beginning of Period	(180,504)	(93,883)
Net current period change	28,709	(86,621)
Reclassification to interest expense from interest rate swaps	0	0
Balance as of End of Period	(151,795)	(180,504)
Digital Realty Trust, L.P. | Cash flow hedge adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance as of Beginning of Period	4,191	(7,081)
Net current period change	6,108	6,304
Reclassification to interest expense from interest rate swaps	2,459	4,968
Balance as of End of Period	12,758	4,191
Digital Realty Trust, L.P. | Foreign currency net investment hedge adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance as of Beginning of Period	35,694	0
Net current period change	(9,542)	35,694
Reclassification to interest expense from interest rate swaps	0	0
Balance as of End of Period	26,152	35,694
Digital Realty Trust, L.P. | Accumulated Other Comprehensive Income (Loss), net
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance as of Beginning of Period	(140,619)	(100,964)
Net current period change	25,275	(44,623)
Reclassification to interest expense from interest rate swaps	2,459	4,968
Balance as of End of Period	$ (112,885)	$ (140,619)