Income per Unit (Schedule of Antidilutive Securities Excluded from Computation of Earnings per Share) (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (units)	19,036,184	12,245,217	19,993,742	11,487,387
Digital Realty Trust, L.P.
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (units)	10,865,272	8,978,766	11,725,360	8,920,621
Digital Realty Trust, L.P. | Potentially dilutive Series C Cumulative Redeemable Perpetual Preferred Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (units)	1,727,724	329,709	1,864,489	109,903
Digital Realty Trust, L.P. | Potentially dilutive Series F Cumulative Redeemable Preferred Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (units)	0	0	0	617,734
Digital Realty Trust, L.P. | Potentially dilutive Series G Cumulative Redeemable Preferred Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (units)	2,142,282	2,193,331	2,311,864	2,262,875
Digital Realty Trust, L.P. | Potentially dilutive Series H Cumulative Redeemable Preferred Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (units)	3,139,291	3,214,098	3,387,795	3,316,008
Digital Realty Trust, L.P. | Potentially dilutive Series I Cumulative Redeemable Preferred Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (units)	2,144,789	2,195,898	2,314,569	2,265,524
Digital Realty Trust, L.P. | Potentially dilutive Series J Cumulative Redeemable Preferred Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (units)	1,711,186	1,045,730	1,846,643	348,577