Debt of the Operating Partnership (Weighted-average Interest Rate by Denomination of Draw) (Details) - Digital Realty Trust, L.P. $ in Thousands	Sep. 30, 2018 USD ($) $ / $ $ / ¥ $ / £ $ / $ $ / $ $ / $	Dec. 31, 2017 USD ($) $ / $ $ / ¥ $ / £ $ / $ $ / $ $ / $
Debt Instrument [Line Items]
Long-term debt, gross	$ 9,242,935
Unsecured Term Loans
Debt Instrument [Line Items]
Long-term debt, gross	$ 1,356,702	$ 1,425,117
Weighted-average interest rate	2.94%	2.42%
Senior Notes
Debt Instrument [Line Items]
Long-term debt, gross	$ 7,185,320
Interest Rate Swap | Unsecured Term Loans
Debt Instrument [Line Items]
Weighted-average interest rate	2.55%	2.41%
U.S. dollar ($) | Unsecured Term Loans
Debt Instrument [Line Items]
Long-term debt, gross	$ 606,911	$ 606,911
Weighted-average interest rate	3.47%	2.78%
U.S. dollar ($) | Interest Rate Swap | Unsecured Term Loans
Debt Instrument [Line Items]
Weighted-average interest rate	2.72%	2.72%
British pound sterling (£) | Unsecured Term Loans
Debt Instrument [Line Items]
Long-term debt, gross	$ 220,843	$ 229,011
Weighted-average interest rate	1.82%	1.59%
Exchange rate | $ / £	1.30	1.35
British pound sterling (£) | Interest Rate Swap | Unsecured Term Loans
Debt Instrument [Line Items]
Weighted-average interest rate	1.89%	1.89%
Singapore dollar (SGD) | Unsecured Term Loans
Debt Instrument [Line Items]
Long-term debt, gross	$ 189,713	$ 233,788
Weighted-average interest rate	2.68%	2.17%
Exchange rate | $ / $	0.73	0.75
Australian dollar (AUD) | Unsecured Term Loans
Debt Instrument [Line Items]
Long-term debt, gross	$ 166,369	$ 179,841
Weighted-average interest rate	2.94%	2.79%
Exchange rate | $ / $	0.72	0.78
Hong Kong dollar (HKD) | Unsecured Term Loans
Debt Instrument [Line Items]
Long-term debt, gross	$ 85,221	$ 85,762
Weighted-average interest rate	2.80%	2.20%
Exchange rate | $ / $	0.13	0.13
Canadian dollar (CAD) | Unsecured Term Loans
Debt Instrument [Line Items]
Long-term debt, gross	$ 76,298	$ 78,357
Weighted-average interest rate	2.93%	2.44%
Exchange rate | $ / $	0.77	0.80
Canadian dollar (CAD) | Interest Rate Swap | Unsecured Term Loans
Debt Instrument [Line Items]
Weighted-average interest rate	1.88%	1.88%
Japanese yen (JPY) | Unsecured Term Loans
Debt Instrument [Line Items]
Long-term debt, gross	$ 11,347	$ 11,447
Weighted-average interest rate	1.01%	1.05%
Exchange rate | $ / ¥	0.01	0.01