Income per Unit (Schedule of Antidilutive Securities Excluded From Computation of Earnings Per Share) (Details) - shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (in shares)	20,028,886	13,559,863	16,421,253
Potentially dilutive Series E Cumulative Redeemable Preferred Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (in shares)	0	0	2,880,254
Digital Realty Trust, L.P.
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (in shares)	11,801,423	9,563,313	14,015,235
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 (in shares)	1,876,584	540,773	0
Digital Realty Trust, L.P. | Potentially dilutive Series E Cumulative Redeemable Preferred Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (in shares)	0	0	2,880,254
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 (in shares)	0	463,301	1,939,905
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 (in shares)	2,326,861	2,261,153	2,652,503
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 (in shares)	3,409,772	3,313,484	3,886,966
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 (in shares)	2,329,584	2,263,799	2,655,607
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 (in shares)	1,858,622	720,803	0