Capital and Accumulated Other Comprehensive Loss (Schedule of Accumulated Other Comprehensive Loss) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2018 USD ($)
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Net current period change	$ 7,433
Reclassification to interest expense from interest rate swaps	(2,202)
Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Net current period change	(8,272)
Reclassification to interest expense from interest rate swaps	0
Cash flow hedge adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Net current period change	15,705
Reclassification to interest expense from interest rate swaps	(2,202)
Foreign currency net investment hedge adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Net current period change	0
Reclassification to interest expense from interest rate swaps	0
Digital Realty Trust, L.P.
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	11,049,450
Net current period change	7,728
Reclassification to interest expense from interest rate swaps	(2,289)
Ending Balance	10,763,462
Digital Realty Trust, L.P. | Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(151,795)
Net current period change	(8,608)
Reclassification to interest expense from interest rate swaps	0
Ending Balance	(160,403)
Digital Realty Trust, L.P. | Cash flow hedge adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	12,758
Net current period change	16,336
Reclassification to interest expense from interest rate swaps	(2,289)
Ending Balance	26,805
Digital Realty Trust, L.P. | Foreign currency net investment hedge adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	26,152
Net current period change	0
Reclassification to interest expense from interest rate swaps	0
Ending Balance	26,152
Digital Realty Trust, L.P. | Accumulated other comprehensive income (loss), net
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(112,885)
Ending Balance	$ (107,446)