Income per Share (Schedule of Antidilutive Securities Excluded From Computation Of Earnings Per Share) (Details) - shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (in shares)	16,421,253	20,118,783	21,429,247
Weighted average of Operating Partnership common units not owned by Digital Realty Trust, Inc.
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (in shares)	2,406,018	2,658,291	2,753,614
Potentially dilutive 2029 Debentures
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (in shares)	0	0	1,957,963
Potentially dilutive Series E Cumulative Redeemable Preferred Stock and Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (in shares)	2,880,254	4,301,438	4,956,175
Potentially dilutive Series F Cumulative Redeemable Preferred Stock and Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (in shares)	1,939,905	2,727,962	3,143,195
Potentially dilutive Series G Cumulative Redeemable Preferred Stock and Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (in shares)	2,652,503	3,730,042	4,297,805
Potentially dilutive Series H Cumulative Redeemable Preferred Stock and Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (in shares)	3,886,966	5,465,987	4,320,495
Potentially dilutive Series I Cumulative Redeemable Preferred Stock and Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (in shares)	2,655,607	1,235,063	0