Derivative Instruments (Details) £ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2017	Dec. 31, 2017 GBP (£)	Dec. 31, 2017 $ / SGD	Dec. 31, 2017 $ / €	Dec. 31, 2017 $ / £	Dec. 31, 2017 $ / CAD	Dec. 31, 2017 $ / AUD	Dec. 31, 2017 instrument	Dec. 31, 2016 $ / SGD	Dec. 31, 2016 $ / €	Dec. 31, 2016 $ / ¥	Dec. 31, 2016 $ / £	Dec. 31, 2016 $ / CAD	Dec. 31, 2016 $ / AUD	Dec. 31, 2016 $ / HKD	Jul. 01, 2016 instrument	Jun. 30, 2016 USD ($)
Derivative [Line Items]
Ineffective portion of cash flow hedges	$ 0	$ 0	$ 0
Notional Amount	1,018,274,000	1,124,181,000
Gain (loss) to be reclassified within twelve months	1,600,000
Excess proceeds from forward contract settlement	63,956,000	0	0
Digital Realty Trust, L.P.
Derivative [Line Items]
Excess proceeds from forward contract settlement	$ 63,956,000	0	$ 0
Digital Realty Trust, L.P. | Unsecured term loan — 5-year
Derivative [Line Items]
Debt instrument term	5 years
Digital Realty Trust, L.P. | Unsecured term loan — 7-year
Derivative [Line Items]
Debt instrument term	7 years
Digital Realty Trust, L.P. | Unsecured term loan
Derivative [Line Items]
Derivative forward exchange rate (in dollars per share)						0.75	1.20	1.35		0.78		0.69	1.05	0.01	1.23	0.74	0.72	0.13
Digital Realty Trust, L.P. | Unsecured term loan | Singapore dollar (SGD)
Derivative [Line Items]
Derivative forward exchange rate (in dollars per share) | $ / SGD												0.69
Digital Realty Trust, L.P. | Unsecured term loan | British pound sterling (£)
Derivative [Line Items]
Derivative forward exchange rate (in dollars per share) | $ / £								1.35							1.23
Digital Realty Trust, L.P. | Unsecured term loan | Canadian dollar (CAD)
Derivative [Line Items]
Derivative forward exchange rate (in dollars per share) | $ / CAD									0.80							0.74
Level 2
Derivative [Line Items]
Fair Value at Significant Other Observable Inputs (Level 2)	$ 18,572,000	11,208,000
Interest Rate Swap, 1.611
Derivative [Line Items]
Notional Amount	206,000,000	0
Strike Rate				1.611%
Interest Rate Swap, 1.611 | Level 2
Derivative [Line Items]
Fair Value at Significant Other Observable Inputs (Level 2)	1,409,000	0
Interest Rate Swap,1.605
Derivative [Line Items]
Notional Amount	54,905,000	0
Strike Rate				1.605%
Interest Rate Swap,1.605 | Level 2
Derivative [Line Items]
Fair Value at Significant Other Observable Inputs (Level 2)	374,000	0
Interest Rate Swap, 0.932
Derivative [Line Items]
Notional Amount	0	206,000,000
Strike Rate				0.932%
Interest Rate Swap, 0.932 | Level 2
Derivative [Line Items]
Fair Value at Significant Other Observable Inputs (Level 2)	0	(90,000)
Interest Rate Swap, 0.670
Derivative [Line Items]
Notional Amount	0	54,905,000
Strike Rate				0.67%
Interest Rate Swap, 0.670 | Level 2
Derivative [Line Items]
Fair Value at Significant Other Observable Inputs (Level 2)	0	16,000
Interest Rate Swap, 1.016
Derivative [Line Items]
Notional Amount	75,000,000	75,000,000
Strike Rate				1.016%
Interest Rate Swap, 1.016 | Level 2
Derivative [Line Items]
Fair Value at Significant Other Observable Inputs (Level 2)	2,260,000	1,911,000
Interest Rate Swap, 1.164
Derivative [Line Items]
Notional Amount	75,000,000	75,000,000
Strike Rate				1.164%
Interest Rate Swap, 1.164 | Level 2
Derivative [Line Items]
Fair Value at Significant Other Observable Inputs (Level 2)	1,947,000	1,487,000
Interest Rate Swap, 1.435
Derivative [Line Items]
Notional Amount	300,000,000	300,000,000
Strike Rate				1.435%
Interest Rate Swap, 1.435 | Level 2
Derivative [Line Items]
Fair Value at Significant Other Observable Inputs (Level 2)	9,978,000	8,128,000
Interest Rate Swap, 0.925
Derivative [Line Items]
Notional Amount	0	130,850,000
Strike Rate				0.925%
Interest Rate Swap, 0.925 | Level 2
Derivative [Line Items]
Fair Value at Significant Other Observable Inputs (Level 2)	0	18,000
Interest Rate Swap, 0.792
Derivative [Line Items]
Notional Amount	229,012,000	209,132,000
Strike Rate				0.792%
Interest Rate Swap, 0.792 | Level 2
Derivative [Line Items]
Fair Value at Significant Other Observable Inputs (Level 2)	(430,000)	(1,818,000)
Interest Rate Swap, 0.779
Derivative [Line Items]
Notional Amount	78,357,000	73,294,000
Strike Rate				0.779%
Interest Rate Swap, 0.779 | Level 2
Derivative [Line Items]
Fair Value at Significant Other Observable Inputs (Level 2)	3,034,000	$ 1,556,000
Not Designated as Hedging Instrument [Member] | Currency forward contracts
Derivative [Line Items]
Notional Amount | £					£ 357,300
Fair Value at Significant Other Observable Inputs (Level 2)																				$ 37,800,000
Number of forward contracts | instrument											4								4
Excess proceeds from forward contract settlement	64,000,000
Amount of AOCI to remain in AOCI	26,200,000
Designated as Hedging Instrument | Currency forward contracts | Notional Amount Sold
Derivative [Line Items]
Notional Amount | £					£ 357,299
Designated as Hedging Instrument | Currency forward contracts | Notional Amount Purchased
Derivative [Line Items]
Notional Amount	$ 518,469,000