Digital Realty Trust 10-Q 2 Nov 18 2018 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2018	Oct. 31, 2018
Entity Information [Line Items]
Document Type	10-Q
Document Period End Date	Sep. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Registrant Name	Digital Realty Trust, Inc.
Entity Central Index Key	1,297,996
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		206,282,023
Digital Realty Trust, L.P.
Entity Information [Line Items]
Document Type	10-Q
Document Period End Date	Sep. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Registrant Name	Digital Realty Trust, L.P.
Entity Central Index Key	1,494,877
Entity Filer Category	Non-accelerated Filer

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Properties:
Land	$ 1,226,729	$ 1,136,341
Acquired ground leases	10,762	11,150
Buildings and improvements	16,007,132	15,215,405
Tenant improvements	566,751	553,040
Total investments in properties	17,811,374	16,915,936
Accumulated depreciation and amortization	(3,755,596)	(3,238,227)
Net investments in properties	14,055,778	13,677,709
Investments in unconsolidated joint ventures	169,919	163,477
Net investments in real estate	14,225,697	13,841,186
Cash and cash equivalents	46,242	51
Accounts and other receivables, net of allowance for doubtful accounts of $9,060 and $6,737 as of September 30, 2018 and December 31, 2017, respectively	308,709	276,347
Deferred rent	454,412	430,026
Acquired above-market leases, net	135,127	184,375
Goodwill	3,373,342	3,389,595
Acquired in-place lease value, deferred leasing costs and intangibles, net	2,734,158	2,998,806
Restricted cash	8,068	13,130
Assets held for sale	0	139,538
Other assets	176,355	131,291
Total assets	21,462,110	21,404,345
LIABILITIES AND EQUITY
Unsecured senior notes, net	7,130,541	6,570,757
Mortgage loans, including premiums, net	106,072	106,582
Accounts payable and other accrued liabilities	1,059,355	980,218
Accrued dividends and distributions	0	199,761
Acquired below-market leases, net	208,202	249,465
Security deposits and prepaid rents	233,667	217,898
Obligations associated with assets held for sale	0	5,033
Total liabilities	10,681,095	10,300,993
Redeemable noncontrolling interests – operating partnership	17,553	53,902
Commitments and contingencies
Stockholders’ Equity:
Preferred stock/units	1,249,560	1,249,560
Common Stock: $0.01 par value per share, 315,000,000 shares authorized, 206,267,055 and 205,470,300 shares issued and outstanding as of September 30, 2018 and December 31, 2017, respectively	2,049	2,044
Partners’ capital:
Additional paid-in capital	11,333,035	11,261,461
Accumulated dividends in excess of earnings	(2,455,189)	(2,055,552)
Accumulated other comprehensive loss, net	(103,201)	(108,432)
Total stockholders’ equity	10,026,254	10,349,081
Noncontrolling Interests:
Noncontrolling interests in operating partnership	671,269	698,126
Noncontrolling interests in consolidated joint ventures	65,939	2,243
Total noncontrolling interests	737,208	700,369
Total equity	10,763,462	11,049,450
Total liabilities and equity/capital	21,462,110	21,404,345
Digital Realty Trust, L.P.
Properties:
Land	1,226,729	1,136,341
Acquired ground leases	10,762	11,150
Buildings and improvements	16,007,132	15,215,405
Tenant improvements	566,751	553,040
Total investments in properties	17,811,374	16,915,936
Accumulated depreciation and amortization	(3,755,596)	(3,238,227)
Net investments in properties	14,055,778	13,677,709
Investments in unconsolidated joint ventures	169,919	163,477
Net investments in real estate	14,225,697	13,841,186
Cash and cash equivalents	46,242	51
Accounts and other receivables, net of allowance for doubtful accounts of $9,060 and $6,737 as of September 30, 2018 and December 31, 2017, respectively	308,709	276,347
Deferred rent	454,412	430,026
Acquired above-market leases, net	135,127	184,375
Goodwill	3,373,342	3,389,595
Acquired in-place lease value, deferred leasing costs and intangibles, net	2,734,158	2,998,806
Restricted cash	8,068	13,130
Assets held for sale	0	139,538
Other assets	176,355	131,291
Total assets	21,462,110	21,404,345
LIABILITIES AND EQUITY
Unsecured senior notes, net	7,130,541	6,570,757
Mortgage loans, including premiums, net	106,072	106,582
Accounts payable and other accrued liabilities	1,059,355	980,218
Accrued dividends and distributions	0	199,761
Acquired below-market leases, net	208,202	249,465
Security deposits and prepaid rents	233,667	217,898
Obligations associated with assets held for sale	0	5,033
Total liabilities	10,681,095	10,300,993
Redeemable noncontrolling interests – operating partnership	17,553	53,902
Commitments and contingencies
Stockholders’ Equity:
Preferred stock/units	1,249,560	1,249,560
Partners’ capital:
Common units, 206,267,055 and 205,470,300 units issued and outstanding as of September 30, 2018 and December 31, 2017, respectively	8,879,895	9,207,953
Limited Partners, 8,340,587 and 8,489,095 units issued and outstanding as of September 30, 2018 and December 31, 2017, respectively	675,514	702,579
Accumulated other comprehensive loss, net	(107,446)	(112,885)
Total partners’ capital	10,697,523	11,047,207
Noncontrolling Interests:
Noncontrolling interests in consolidated joint ventures	65,939	2,243
Total capital	10,763,462	11,049,450
Total liabilities and equity/capital	21,462,110	21,404,345
Global revolving credit facility, net
LIABILITIES AND EQUITY
Line of credit	590,289	550,946
Global revolving credit facility, net | Digital Realty Trust, L.P.
LIABILITIES AND EQUITY
Line of credit	590,289	550,946
Unsecured term loans, net
LIABILITIES AND EQUITY
Line of credit	1,352,969	1,420,333
Unsecured term loans, net | Digital Realty Trust, L.P.
LIABILITIES AND EQUITY
Line of credit	$ 1,352,969	$ 1,420,333

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Accounts and other receivables, net of allowance for doubtful accounts	$ 9,060	$ 6,737
Preferred stock, par value (in dollars per share/unit)	$ 0.01	$ 0.01
Preferred stock, authorized (shares)	110,000,000	110,000,000
Preferred stock, issued (shares)	50,650,000	50,650,000
Preferred stock, outstanding (shares)	50,650,000	50,650,000
Common stock, par value (in dollars per share/unit)	$ 0.01	$ 0.01
Common stock, authorized (shares)	315,000,000	315,000,000
Common stock, shares, issued (shares)	206,267,055	205,470,300
Common stock, shares, outstanding (shares)	206,267,055	205,470,300
Digital Realty Trust, L.P.
Accounts and other receivables, net of allowance for doubtful accounts	$ 9,060	$ 6,737
Preferred units, issued (units)	50,650,000	50,650,000
Preferred units, outstanding (units)	50,650,000	50,650,000
Common units, issued (units)	206,267,055	205,470,300
Common units, outstanding (units)	206,267,055	205,470,300
Limited Partners' units, issued (units)	8,340,587	8,489,095
Limited Partners' units outstanding (units)	8,340,587	8,489,095

Condensed Consolidated Income S

Condensed Consolidated Income Statements - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Operating Revenues:
Rental and other services	$ 603,833	$ 500,442	$ 1,792,457	$ 1,432,670
Tenant reimbursements	163,104	107,613	468,906	288,243
Fee income	1,469	1,662	4,945	4,986
Other	518	208	1,903	584
Total operating revenues	768,924	609,925	2,268,211	1,726,483
Operating Expenses:
Rental property operating and maintenance	245,971	190,061	701,933	534,116
Property taxes	34,871	32,586	97,418	87,666
Insurance	2,653	2,590	8,990	7,758
Depreciation and amortization	293,957	199,914	887,534	554,491
General and administrative	41,642	43,765	124,264	115,921
Transactions and integration	9,626	42,809	19,410	60,367
Impairment of investments in real estate	0	28,992	0	28,992
Other	1,139	3,051	1,722	3,075
Total operating expenses	629,859	543,768	1,841,271	1,392,386
Operating income	139,065	66,157	426,940	334,097
Other Income (Expenses):
Equity in earnings of unconsolidated joint ventures	8,886	5,880	23,734	19,592
Gain on sale of properties	26,577	9,750	80,042	9,608
Interest and other income (expense)	(981)	2,813	2,375	3,331
Interest expense	(80,851)	(71,621)	(236,646)	(184,653)
Tax expense	(2,432)	(2,494)	(7,927)	(7,356)
Gain from early extinguishment of debt	0	1,990	0	1,990
Net income	90,264	12,475	288,518	176,609
Net income attributable to noncontrolling interests	(2,667)	(40)	(8,831)	(1,985)
Net income attributable to Digital Realty Trust, Inc./Digital Realty Trust, L.P.	87,597	12,435	279,687	174,624
Preferred stock/unit dividends/distributions, including undeclared distributions	(20,329)	(16,575)	(60,987)	(48,473)
Issuance costs associated with redeemed preferred stock/units	0	0	0	(6,309)
Net income (loss) available to common stock/unitholders	$ 67,268	$ (4,140)	$ 218,700	$ 119,842
Net income (loss) per share/unit available to common stockholders/unitholders:
Basic (in dollars per share/unit)	$ 0.33	$ (0.02)	$ 1.06	$ 0.73
Diluted (in dollars per share/unit)	$ 0.33	$ (0.02)	$ 1.06	$ 0.73
Weighted average common shares/units outstanding:
Basic (shares/units)	206,118,472	170,194,254	205,931,031	163,481,306
Diluted (shares/units)	206,766,256	170,194,254	206,555,627	164,371,096
Digital Realty Trust, L.P.
Operating Revenues:
Rental and other services	$ 603,833	$ 500,442	$ 1,792,457	$ 1,432,670
Tenant reimbursements	163,104	107,613	468,906	288,243
Fee income	1,469	1,662	4,945	4,986
Other	518	208	1,903	584
Total operating revenues	768,924	609,925	2,268,211	1,726,483
Operating Expenses:
Rental property operating and maintenance	245,971	190,061	701,933	534,116
Property taxes	34,871	32,586	97,418	87,666
Insurance	2,653	2,590	8,990	7,758
Depreciation and amortization	293,957	199,914	887,534	554,491
General and administrative	41,642	43,765	124,264	115,921
Transactions and integration	9,626	42,809	19,410	60,367
Impairment of investments in real estate	0	28,992	0	28,992
Other	1,139	3,051	1,722	3,075
Total operating expenses	629,859	543,768	1,841,271	1,392,386
Operating income	139,065	66,157	426,940	334,097
Other Income (Expenses):
Equity in earnings of unconsolidated joint ventures	8,886	5,880	23,734	19,592
Gain on sale of properties	26,577	9,750	80,042	9,608
Interest and other income (expense)	(981)	2,813	2,375	3,331
Interest expense	(80,851)	(71,621)	(236,646)	(184,653)
Tax expense	(2,432)	(2,494)	(7,927)	(7,356)
Gain from early extinguishment of debt	0	1,990	0	1,990
Net income	90,264	12,475	288,518	176,609
Net income attributable to noncontrolling interests	33	(119)	49	(353)
Net income attributable to Digital Realty Trust, Inc./Digital Realty Trust, L.P.	90,297	12,356	288,567	176,256
Preferred stock/unit dividends/distributions, including undeclared distributions	(20,329)	(16,575)	(60,987)	(48,473)
Issuance costs associated with redeemed preferred stock/units	0	0	0	(6,309)
Net income (loss) available to common stock/unitholders	$ 69,968	$ (4,219)	$ 227,580	$ 121,474
Net income (loss) per share/unit available to common stockholders/unitholders:
Basic (in dollars per share/unit)	$ 0.33	$ (0.02)	$ 1.06	$ 0.73
Diluted (in dollars per share/unit)	$ 0.33	$ (0.02)	$ 1.06	$ 0.73
Weighted average common shares/units outstanding:
Basic (shares/units)	214,289,384	173,460,704	214,199,414	166,048,072
Diluted (shares/units)	214,937,168	173,460,704	214,824,010	166,937,862

Condensed Consolidated Statemen

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Net income	$ 90,264	$ 12,475	$ 288,518	$ 176,609
Other comprehensive income (loss):
Foreign currency translation adjustments	2,368	(4,301)	(8,608)	25,954
Increase (decrease) in fair value of interest rate swaps and foreign currency hedges	2,925	(2,234)	16,336	(8,926)
Reclassification to interest expense from interest rate swaps	(1,271)	396	(2,289)	2,073
Comprehensive income	94,286	6,336	293,957	195,710
Comprehensive (income) loss attributable to noncontrolling interests	(2,820)	76	(9,039)	(2,213)
Comprehensive income attributable to Digital Realty Trust, Inc./Digital Realty Trust, L.P.	91,466	6,412	284,918	193,497
Digital Realty Trust, L.P.
Net income	90,264	12,475	288,518	176,609
Other comprehensive income (loss):
Foreign currency translation adjustments	2,368	(4,301)	(8,608)	25,954
Increase (decrease) in fair value of interest rate swaps and foreign currency hedges	2,925	(2,234)	16,336	(8,926)
Reclassification to interest expense from interest rate swaps	(1,271)	396	(2,289)	2,073
Comprehensive income	94,286	6,336	293,957	195,710
Comprehensive (income) loss attributable to noncontrolling interests	33	(119)	49	(353)
Comprehensive income attributable to Digital Realty Trust, Inc./Digital Realty Trust, L.P.	$ 94,319	$ 6,217	$ 294,006	$ 195,357

Condensed Consolidated Statem_2

Condensed Consolidated Statement of Equity - USD ($) $ in Thousands	Total	Redeemable Noncontrolling Interests -- Operating Partnership	Preferred Stock	Common Stock	Additional Paid-in Capital	Accumulated Dividends in Excess of Earnings	Accumulated Other Comprehensive Loss, Net	Total Stockholders’ Equity	Noncontrolling Interests in Operating Partnership	Noncontrolling Interests in Consolidated Joint Ventures	Total Noncontrolling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect adjustment from adoption of new accounting standard	$ 5,915					$ 5,915		$ 5,915
Beginning balance at Dec. 31, 2017	11,049,450	$ 53,902	$ 1,249,560	$ 2,044	$ 11,261,461	(2,055,552)	$ (108,432)	10,349,081	$ 698,126	$ 2,243	$ 700,369
Beginning balance (shares) at Dec. 31, 2017				205,470,300
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of common units to common stock				$ 6	49,690			49,696	(49,696)		(49,696)
Conversion of common units to common stock (shares)				567,792
Issuance of unvested restricted stock, net of forfeitures (shares)				206,264
Issuance of common stock, net of offering costs	(1,292)				(1,292)			(1,292)
Shares issued under employee stock purchase plan	5,874				5,874			5,874
Shares issued under employee stock purchase plan (shares)				69,532
Shares repurchased and retired to satisfy tax withholding upon vesting	(4,952)			$ (1)	(4,951)			(4,952)
Shares repurchased and retired to satisfy tax withholding upon vesting (shares)				(46,833)
Amortization of share-based compensation	25,213				25,213			25,213
Reclassification of vested share-based awards					(3,631)			(3,631)	3,631		3,631
Adjustment to redeemable noncontrolling interests—operating partnership	36,349	(36,349)			671			671	35,678		35,678
Dividends declared on preferred stock	(60,987)					(60,987)		(60,987)
Dividends and distributions on common stock and common and incentive units	(649,810)					(624,252)		(624,252)	(25,558)		(25,558)
Contributions from noncontrolling interests in consolidated joint ventures, net of distributions	63,745									63,745	63,745
Net income	288,518					279,687		279,687	8,880	(49)	8,831
Other comprehensive loss—foreign currency translation adjustments	(8,608)						(8,272)	(8,272)	(336)		(336)
Other comprehensive income—fair value of interest rate swaps	16,336						15,705	15,705	631		631
Other comprehensive loss—reclassification of accumulated other comprehensive income to interest expense	(2,289)						(2,202)	(2,202)	(87)		(87)
Ending balance at Sep. 30, 2018	$ 10,763,462	$ 17,553	$ 1,249,560	$ 2,049	$ 11,333,035	$ (2,455,189)	$ (103,201)	$ 10,026,254	$ 671,269	$ 65,939	$ 737,208
Ending balance (shares) at Sep. 30, 2018				206,267,055

Condensed Consolidated Statem_3

Condensed Consolidated Statement of Capital - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018	Dec. 31, 2017
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance (units)		205,470,300
Conversion of limited partner common units to general partner common units		$ 49,696
Units issued in connection with employee stock purchase plan		5,874
Shares repurchased and retired to satisfy tax withholding upon vesting		(4,952)
Amortization of share-based compensation		25,213
Cumulative effect adjustment from adoption of new accounting standard			$ 5,915
Net income	$ 90,264	288,518
Other comprehensive loss—foreign currency translation adjustments	2,368	(8,608)
Other comprehensive income—fair value of interest rate swaps	2,925	16,336
Other comprehensive loss—reclassification of accumulated other comprehensive income to interest expense	$ (1,271)	$ (2,289)
Ending balance (units)	206,267,055	206,267,055
Digital Realty Trust, L.P.
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance		$ 11,049,450
Issuance of common units, net of offering costs		(1,292)
Units issued in connection with employee stock purchase plan		5,874
Shares repurchased and retired to satisfy tax withholding upon vesting		(4,952)
Amortization of share-based compensation		25,213
Adjustment to redeemable partnership units		36,349
Distributions		(710,797)
Contributions from noncontrolling interests in consolidated joint ventures, net of distributions		63,745
Cumulative effect adjustment from adoption of new accounting standard			5,915
Net income	$ 90,264	288,518
Other comprehensive loss—foreign currency translation adjustments	2,368	(8,608)
Other comprehensive income—fair value of interest rate swaps	2,925	16,336
Other comprehensive loss—reclassification of accumulated other comprehensive income to interest expense	(1,271)	(2,289)
Ending Balance	10,763,462	10,763,462
Redeemable Limited Partner Common Units | Digital Realty Trust, L.P.
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance		53,902
Adjustment to redeemable partnership units		(36,349)
Ending Balance	17,553	17,553
Accumulated Other Comprehensive Loss | Digital Realty Trust, L.P.
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance		(112,885)
Other comprehensive loss—foreign currency translation adjustments		(8,608)
Other comprehensive income—fair value of interest rate swaps		16,336
Other comprehensive loss—reclassification of accumulated other comprehensive income to interest expense		(2,289)
Ending Balance	(107,446)	(107,446)
Noncontrolling Interests in Consolidated Joint Ventures | Digital Realty Trust, L.P.
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance		2,243
Contributions from noncontrolling interests in consolidated joint ventures, net of distributions		63,745
Net income		(49)
Ending Balance	65,939	65,939
General Partner | Preferred Units | Digital Realty Trust, L.P.
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance		$ 1,249,560
Beginning balance (units)		50,650,000
Distributions		$ (60,987)
Net income		60,987
Ending Balance	$ 1,249,560	$ 1,249,560
Ending balance (units)	50,650,000	50,650,000
General Partner | Common Units | Digital Realty Trust, L.P.
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance		$ 9,207,953
Beginning balance (units)		205,470,300
Conversion of limited partner common units to general partner common units		$ 49,696
Conversion of limited partner common units to general partner common units (units)		567,792
Issuance of unvested restricted common units (units)		206,264
Issuance of common units, net of offering costs		$ (1,292)
Common unit offering costs, net (units)		0
Units issued in connection with employee stock purchase plan		$ 5,874
Units issued in connection with employee stock purchase plan (units)		69,532
Shares repurchased and retired to satisfy tax withholding upon vesting		$ (4,952)
Units repurchased and retired to satisfy tax withholding upon vesting (units)		(46,833)
Amortization of share-based compensation		$ 25,213
Reclassification of vested share-based awards		(3,631)
Adjustment to redeemable partnership units		671
Distributions		(624,252)
Cumulative effect adjustment from adoption of new accounting standard			$ 5,915
Net income		218,700
Ending Balance	$ 8,879,895	$ 8,879,895
Ending balance (units)	206,267,055	206,267,055
Limited Partners | Common Units | Digital Realty Trust, L.P.
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning balance		$ 702,579
Beginning balance (units)		8,489,095
Conversion of limited partner common units to general partner common units		$ (49,696)
Conversion of limited partner common units to general partner common units (units)		(567,792)
Issuance of common units, net of forfeitures (units)		419,284
Reclassification of vested share-based awards		$ 3,631
Adjustment to redeemable partnership units		35,678
Distributions		(25,558)
Net income		8,880
Ending Balance	$ 675,514	$ 675,514
Ending balance (units)	8,340,587	8,340,587

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2017USD ($)	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)
Cash flows from operating activities:
Net income	$ 12,475	$ 288,518	$ 176,609
Adjustments to reconcile net income to net cash provided by operating activities:
Gain on sale of properties	(9,750)	(80,042)	(9,608)
Unrealized gain on equity investment		(2,005)	0
Impairment of investments in real estate	28,992	0	28,992
Equity in earnings of unconsolidated joint ventures	(5,880)	(23,734)	(19,592)
Distributions from unconsolidated joint ventures		15,487	26,592
Write-off of net assets due to early lease terminations		1,723	3,075
Depreciation and amortization of buildings and improvements, tenant improvements and acquired ground leases		570,179	409,229
Amortization of acquired in-place lease value and deferred leasing costs		317,355	145,262
Amortization of share-based compensation		21,177	15,590
Non-cash amortization of terminated swaps		858	903
Allowance for (recovery of) doubtful accounts		2,594	(1,320)
Amortization of deferred financing costs		8,926	7,572
Gain on early extinguishment of debt		0	(1,990)
Amortization of debt discount/premium		2,590	2,156
Amortization of acquired above-market leases and acquired below-market leases, net		20,008	(4,857)
Changes in assets and liabilities:
Accounts and other receivables		(37,498)	(41,713)
Deferred rent		(29,474)	(7,873)
Deferred leasing costs		(18,986)	(14,847)
Other assets		(20,794)	(1,635)
Accounts payable and other accrued liabilities		3,671	(52,597)
Security deposits and prepaid rents		(6,704)	21,603
Net cash provided by operating activities		1,033,849	681,551
Cash flows from investing activities:
Acquisitions of real estate		(116,990)	(44,354)
Proceeds from sale of properties, net of sales costs		286,204	20,200
Excess proceeds from forward contracts		0	63,956
Investments in unconsolidated joint ventures		(463)	(7,614)
Prepaid construction costs and other investments		(13,514)	0
Improvements to investments in real estate		(946,118)	(763,877)
Improvement advances to tenants		(35,223)	(37,271)
Collection of improvement advances to tenants		32,328	30,340
Cash assumed in DFT merger		0	20,650
Net cash used in investing activities		(793,776)	(717,970)
Cash flows from financing activities:
Borrowings on global revolving credit facility		1,079,673	1,499,691
Repayments on global revolving credit facility		(1,045,816)	(2,035,808)
Repayments on unsecured term loans		(39,095)	(354,000)
Borrowings on unsecured senior notes		649,038	2,265,060
Repayments on unsecured senior notes		0	(669,109)
Principal payments on mortgage loans		(440)	(105,406)
Borrowings on mortgage loans		0	104,000
Payment of loan fees and costs		(6,272)	(15,643)
Capital contributions from (distributions paid to) noncontrolling interests in consolidated joint ventures, net		63,745	(365)
Taxes paid related to net settlement of stock-based compensation awards		(4,952)	0
Proceeds from common and preferred stock offerings, net		(1,292)	405,237
Redemption of preferred stock		0	(182,500)
Proceeds from equity plans		5,874	5,872
Proceeds from forward swap contract		1,560	0
Payment of dividends/distributions to preferred stockholders/unitholders		(60,987)	(46,268)
Payment of dividends/distributions to common stockholders/unitholders and distributions to noncontrolling interests in operating partnership		(849,571)	(647,217)
Net cash (used in) provided by financing activities		(208,535)	223,544
Net increase in cash, cash equivalents and restricted cash		31,538	187,125
Effect of exchange rate changes on cash, cash equivalents and restricted cash		9,591	1,170
Cash, cash equivalents and restricted cash at beginning of period		13,181	22,036
Cash, cash equivalents and restricted cash at end of period	210,331	54,310	210,331
Supplemental disclosure of cash flow information:
Cash paid for interest, net of amounts capitalized		247,652	167,148
Cash paid for income taxes		7,861	8,454
Supplementary disclosure of noncash investing and financing activities:
Change in net assets related to foreign currency translation adjustments		(8,608)	25,954
Increase (decrease) in accounts payable and other accrued liabilities related to change in fair value of interest rate swaps and foreign currency hedges		16,336	(8,926)
Acquisition measurement period adjustment to goodwill and accounts payable and other accrued liabilities		0	2,162
Noncontrolling interests in operating partnership converted to shares of common stock		49,696	6,915
Accrual for additions to investments in real estate and tenant improvement advances included in accounts payable and accrued expenses		193,615	232,459
Addition to leasehold improvements pursuant to capital lease obligation		73,873	0
Allocation of purchase price of real estate/investment in partnership to:
Investments in real estate		116,990	43,585
Acquired below-market leases		0	(684)
Acquired in-place lease value and deferred leasing costs		0	1,453
Cash paid for acquisition of real estate		116,990	44,354
Assets and liabilities assumed in DFT merger:
Goodwill		3,373,342
Redeemable noncontrolling interests -- operating partnership	(66,259)		(66,259)
Issuance of preferred stock in connection with merger		1,292
Digital Realty Trust, L.P.
Cash flows from operating activities:
Net income	12,475	288,518	176,609
Adjustments to reconcile net income to net cash provided by operating activities:
Gain on sale of properties	(9,750)	(80,042)	(9,608)
Unrealized gain on equity investment		(2,005)	0
Impairment of investments in real estate	28,992	0	28,992
Equity in earnings of unconsolidated joint ventures	(5,880)	(23,734)	(19,592)
Distributions from unconsolidated joint ventures		15,487	26,592
Write-off of net assets due to early lease terminations		1,723	3,075
Depreciation and amortization of buildings and improvements, tenant improvements and acquired ground leases		570,179	409,229
Amortization of acquired in-place lease value and deferred leasing costs		317,355	145,262
Amortization of share-based compensation		21,177	15,590
Non-cash amortization of terminated swaps		858	903
Allowance for (recovery of) doubtful accounts		2,594	(1,320)
Amortization of deferred financing costs		8,926	7,572
Gain on early extinguishment of debt		0	(1,990)
Amortization of debt discount/premium		2,590	2,156
Amortization of acquired above-market leases and acquired below-market leases, net		20,008	(4,857)
Changes in assets and liabilities:
Accounts and other receivables		(37,498)	(41,713)
Deferred rent		(29,474)	(7,873)
Deferred leasing costs		(18,986)	(14,847)
Other assets		(20,794)	(1,635)
Accounts payable and other accrued liabilities		3,671	(52,597)
Security deposits and prepaid rents		(6,704)	21,603
Net cash provided by operating activities		1,033,849	681,551
Cash flows from investing activities:
Acquisitions of real estate		(116,990)	(44,354)
Proceeds from sale of properties, net of sales costs		286,204	20,200
Excess proceeds from forward contracts		0	63,956
Investments in unconsolidated joint ventures		(463)	(7,614)
Prepaid construction costs and other investments		(13,514)	0
Improvements to investments in real estate		(946,118)	(763,877)
Improvement advances to tenants		(35,223)	(37,271)
Collection of improvement advances to tenants		32,328	30,340
Cash assumed in DFT merger		0	20,650
Net cash used in investing activities		(793,776)	(717,970)
Cash flows from financing activities:
Borrowings on global revolving credit facility		1,079,673	1,499,691
Repayments on global revolving credit facility		(1,045,816)	(2,035,808)
Repayments on unsecured term loans		(39,095)	(354,000)
Borrowings on unsecured senior notes		649,038	2,265,060
Repayments on unsecured senior notes		0	(669,109)
Principal payments on mortgage loans		(440)	(105,406)
Borrowings on mortgage loans		0	104,000
Payment of loan fees and costs		(6,272)	(15,643)
Capital contributions from (distributions paid to) noncontrolling interests in consolidated joint ventures, net		63,745	(365)
Taxes paid related to net settlement of stock-based compensation awards		(4,952)	0
General partner contributions, net		4,582	228,609
Proceeds from forward swap contract		1,560	0
Payment of dividends/distributions to preferred stockholders/unitholders		(60,987)	(46,268)
Payment of dividends/distributions to common stockholders/unitholders and distributions to noncontrolling interests in operating partnership		(849,571)	(647,217)
Net cash (used in) provided by financing activities		(208,535)	223,544
Net increase in cash, cash equivalents and restricted cash		31,538	187,125
Effect of exchange rate changes on cash, cash equivalents and restricted cash		9,591	1,170
Cash, cash equivalents and restricted cash at beginning of period		13,181	22,036
Cash, cash equivalents and restricted cash at end of period	210,331	54,310	210,331
Supplemental disclosure of cash flow information:
Cash paid for interest, net of amounts capitalized		247,652	167,148
Cash paid for income taxes		7,861	8,454
Supplementary disclosure of noncash investing and financing activities:
Change in net assets related to foreign currency translation adjustments		(8,608)	25,954
Increase (decrease) in accounts payable and other accrued liabilities related to change in fair value of interest rate swaps and foreign currency hedges		16,336	(8,926)
Acquisition measurement period adjustment to goodwill and accounts payable and other accrued liabilities		0	2,162
Accrual for additions to investments in real estate and tenant improvement advances included in accounts payable and accrued expenses		193,615	232,459
Addition to leasehold improvements pursuant to capital lease obligation		73,873	0
Allocation of purchase price of real estate/investment in partnership to:
Investments in real estate		116,990	43,585
Acquired below-market leases		0	(684)
Acquired in-place lease value and deferred leasing costs		0	1,453
Cash paid for acquisition of real estate		116,990	44,354
Assets and liabilities assumed in DFT merger:
Goodwill		3,373,342
Redeemable noncontrolling interests -- operating partnership	(66,259)		(66,259)
DFT Company
Assets and liabilities assumed in DFT merger:
Cash assumed in merger	20,650		20,650
Land	312,579		312,579
Building and improvements	3,677,497		3,677,497
Accounts and other receivables	10,978		10,978
Intangibles	1,582,385		1,582,385
Goodwill	2,592,181	2,592,146	2,592,181
Accounts payable and other accrued liabilities	(248,259)		(248,259)
Acquired below-market leases	(185,543)		(185,543)
Other working capital, net	(24,630)		(24,630)
DFT Company | Digital Realty Trust, L.P.
Assets and liabilities assumed in DFT merger:
Cash assumed in merger	20,650		20,650
Land	312,579		312,579
Building and improvements	3,677,497		3,677,497
Accounts and other receivables	10,978		10,978
Intangibles	1,582,385		1,582,385
Goodwill	2,592,181		2,592,181
Accounts payable and other accrued liabilities	(248,259)		(248,259)
Acquired below-market leases	(185,543)		(185,543)
Other working capital, net	(24,630)		(24,630)
Above Market Leases | DFT Company
Assets and liabilities assumed in DFT merger:
Acquired above-market leases	162,333		162,333
Above Market Leases | DFT Company | Digital Realty Trust, L.P.
Assets and liabilities assumed in DFT merger:
Acquired above-market leases	162,333		162,333
Global Revolving Credit Facility | DFT Company
Assets and liabilities assumed in DFT merger:
Long term debt	(450,697)		(450,697)
Global Revolving Credit Facility | DFT Company | Digital Realty Trust, L.P.
Assets and liabilities assumed in DFT merger:
Long term debt	(450,697)		(450,697)
Unsecured Term Loans | DFT Company
Assets and liabilities assumed in DFT merger:
Long term debt	(250,000)		(250,000)
Unsecured Term Loans | DFT Company | Digital Realty Trust, L.P.
Assets and liabilities assumed in DFT merger:
Long term debt	(250,000)		(250,000)
Senior Notes | DFT Company
Assets and liabilities assumed in DFT merger:
Long term debt	(884,841)		(884,841)
Senior Notes | DFT Company | Digital Realty Trust, L.P.
Assets and liabilities assumed in DFT merger:
Long term debt	(884,841)		(884,841)
Mortgage Loans | DFT Company
Assets and liabilities assumed in DFT merger:
Long term debt	(105,000)		(105,000)
Mortgage Loans | DFT Company | Digital Realty Trust, L.P.
Assets and liabilities assumed in DFT merger:
Long term debt	$ (105,000)		(105,000)
Parent
Cash flows from operating activities:
Net income		279,687
Assets and liabilities assumed in DFT merger:
Issuance of preferred stock in connection with merger		$ 1,292
Parent | DFT Company
Assets and liabilities assumed in DFT merger:
Common stock/units issued in connection with merger			(5,247,558)
Common Unit | DFT Company
Assets and liabilities assumed in DFT merger:
Common stock/units issued in connection with merger			(676,566)
Series C Preferred Units | DFT Company | Digital Realty Trust, L.P.
Assets and liabilities assumed in DFT merger:
Issuance of preferred stock in connection with merger			(219,250)
Series C Preferred Stock | Preferred Stock | DFT Company
Assets and liabilities assumed in DFT merger:
Issuance of preferred stock in connection with merger			(219,250)
General Partner | Common Unit | DFT Company | Digital Realty Trust, L.P.
Assets and liabilities assumed in DFT merger:
Common stock/units issued in connection with merger			(5,247,558)
Limited Partners | Common Unit | DFT Company | Digital Realty Trust, L.P.
Assets and liabilities assumed in DFT merger:
Common stock/units issued in connection with merger			$ (676,566)

Organization and Description of

Organization and Description of Business	9 Months Ended
	Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Description Of Business	Organization and Description of Business Digital Realty Trust, Inc. through its controlling interest in Digital Realty Trust, L.P. (the Operating Partnership) and the subsidiaries of the Operating Partnership (collectively, we, our, us or the Company) is a leading global provider of data center, colocation and interconnection solutions for customers across a variety of industry verticals ranging from cloud and information technology services, communications and social networking to financial services, manufacturing, energy, healthcare, and consumer products. The Operating Partnership, a Maryland limited partnership, is the entity through which Digital Realty Trust, Inc., a Maryland corporation, conducts its business of owning, acquiring, developing and operating data centers. Digital Realty Trust, Inc. operates as a REIT for federal income tax purposes. A summary of our data center portfolio as of September 30, 2018 and December 31, 2017 is as follows: Data Centers As of September 30, 2018 As of December 31, 2017 Region Operating Held for Sale Unconsolidated Joint Ventures Total Operating Held for Sale Unconsolidated Joint Ventures Total United States 131 — 14 145 131 7 14 152 Europe 38 — — 38 38 — — 38 Asia 3 — 4 7 3 — 4 7 Australia 5 — — 5 5 — — 5 Canada 3 — — 3 3 — — 3 Total 180 — 18 198 180 7 18 205 We are diversified in major metropolitan areas where data center and technology customers are concentrated, including the Atlanta, Boston, Chicago, Dallas, Los Angeles, New York, Northern Virginia, Phoenix, San Francisco, Seattle, Silicon Valley and Toronto metropolitan areas in North America, the Amsterdam, Dublin, Frankfurt, London and Paris metropolitan areas in Europe and the Hong Kong, Melbourne, Osaka, Singapore, Sydney, and Tokyo metropolitan areas in the Asia Pacific region. The portfolio consists of data centers, Internet gateway facilities and office and other non-data center space. The Operating Partnership was formed on July 21, 2004 in anticipation of Digital Realty Trust, Inc.’s initial public offering (IPO) on November 3, 2004 and commenced operations on that date. As of September 30, 2018 , Digital Realty Trust, Inc. owns a 96.1% common interest and a 100.0% preferred interest in the Operating Partnership. As of December 31, 2017 , Digital Realty Trust, Inc. owned a 96.0% common interest and a 100.0% preferred interest in the Operating Partnership. As sole general partner of the Operating Partnership, Digital Realty Trust, Inc. has the full, exclusive and complete responsibility for the Operating Partnership’s day-to-day management and control. The limited partners of the Operating Partnership do not have rights to replace Digital Realty Trust, Inc. as the general partner nor do they have participating rights, although they do have certain protective rights.

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2018
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies (a) Principles of Consolidation and Basis of Presentation The accompanying interim condensed consolidated financial statements include all of the accounts of Digital Realty Trust, Inc., the Operating Partnership and the subsidiaries of the Operating Partnership. Intercompany balances and transactions have been eliminated. The accompanying interim condensed consolidated financial statements are unaudited, but have been prepared in accordance with U.S. generally accepted accounting principles (U.S. GAAP) for interim financial information and in compliance with the rules and regulations of the United States Securities and Exchange Commission. Accordingly, they do not include all of the disclosures required by U.S. GAAP for complete financial statements. In the opinion of management, all adjustments necessary for a fair presentation have been included. All such adjustments are considered to be of a normal recurring nature, except as otherwise indicated. The results of operations for the interim periods are not necessarily indicative of the results to be obtained for the full fiscal year. These condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and the notes thereto included in our annual report on Form 10-K for the year ended December 31, 2017 . The notes to the condensed consolidated financial statements of Digital Realty Trust, Inc. and the Operating Partnership have been combined to provide the following benefits: • enhancing investors’ understanding of the Company and the Operating Partnership by enabling investors to view the business as a whole in the same manner as management views and operates the business; • eliminating duplicative disclosure and providing a more streamlined and readable presentation since a substantial portion of the disclosure applies to both the Company and the Operating Partnership; and • creating time and cost efficiencies through the preparation of one set of notes instead of two separate sets of notes. There are a few differences between the Company and the Operating Partnership, which are reflected in these condensed consolidated financial statements. We believe it is important to understand the differences between the Company and the Operating Partnership in the context of how we operate as an interrelated consolidated company. Digital Realty Trust, Inc.’s only material asset is its ownership of partnership interests of the Operating Partnership. As a result, Digital Realty Trust, Inc. generally does not conduct business itself, other than acting as the sole general partner of the Operating Partnership, issuing public securities from time to time and guaranteeing certain unsecured debt of the Operating Partnership and certain of its subsidiaries and affiliates. Digital Realty Trust, Inc. itself has not issued any indebtedness but guarantees the unsecured debt of the Operating Partnership and certain of its subsidiaries and affiliates, as disclosed in these notes. The Operating Partnership holds substantially all the assets of the Company and holds the ownership interests in the Company’s joint ventures. The Operating Partnership conducts the operations of the business and is structured as a partnership with no publicly traded equity. Except for net proceeds from public equity issuances by Digital Realty Trust, Inc., which are generally contributed to the Operating Partnership in exchange for partnership units, the Operating Partnership generally generates the capital required by the Company’s business primarily through the Operating Partnership’s operations, by the Operating Partnership’s or its affiliates' direct or indirect incurrence of indebtedness or through the issuance of partnership units. The presentation of noncontrolling interests in operating partnership, stockholders’ equity and partners’ capital are the main areas of difference between the condensed consolidated financial statements of Digital Realty Trust, Inc. and those of the Operating Partnership. The common limited partnership interests held by the limited partners in the Operating Partnership are presented as limited partners’ capital within partners’ capital in the Operating Partnership’s condensed consolidated financial statements and as noncontrolling interests in operating partnership within equity in Digital Realty Trust, Inc.’s condensed consolidated financial statements. The common and preferred partnership interests held by Digital Realty Trust, Inc. in the Operating Partnership are presented as general partner’s capital within partners’ capital in the Operating Partnership’s condensed consolidated financial statements and as preferred stock, common stock, additional paid-in capital and accumulated dividends in excess of earnings within stockholders’ equity in Digital Realty Trust, Inc.’s condensed consolidated financial statements. The differences in the presentations between stockholders’ equity and partners’ capital result from the differences in the equity issued at the Digital Realty Trust, Inc. and the Operating Partnership levels. To help investors understand the significant differences between the Company and the Operating Partnership, these consolidated financial statements present the following separate sections for each of the Company and the Operating Partnership: • condensed consolidated face financial statements; and • the following notes to the condensed consolidated financial statements: • "Debt of the Company" and "Debt of the Operating Partnership"; • "Income per Share" and "Income per Unit"; and • "Equity and Accumulated Other Comprehensive Loss, Net of the Company" and "Capital and Accumulated Other Comprehensive Loss of the Operating Partnership". In the sections that combine disclosure of Digital Realty Trust, Inc. and the Operating Partnership, these notes refer to actions or holdings as being actions or holdings of the Company. Although the Operating Partnership is generally the entity that enters into contracts and joint ventures and holds assets and debt, reference to the Company is appropriate because the business is one enterprise and the Company generally operates the business through the Operating Partnership. (b) Cash Equivalents For the purpose of the condensed consolidated statements of cash flows, we consider short-term investments with original maturities of 90 days or less to be cash equivalents. As of September 30, 2018 , cash equivalents consist of investments in money market instruments. (c) Investments in Unconsolidated Joint Ventures The Company’s investments in unconsolidated joint ventures are accounted for using the equity method, whereby our investment is increased for capital contributed and our share of the joint venture's net income and decreased by distributions we receive and our share of any losses of the joint ventures. We do not record losses of the joint ventures in excess of our investment balances unless we are liable for the obligations of the joint venture or are otherwise committed to provide financial support to the joint venture. Likewise, and as long as we have no explicit or implicit obligations to the joint venture, we will suspend equity method accounting to the extent that cash distributions exceed our investment balances until those unrecorded earnings exceed the excess distributions previously recognized in income. In this case, we will apply cost accounting concepts which tie income recognition to the receipt of cash. Cost basis accounting concepts will apply until earnings exceed the excess distributions previously recognized in income. We amortize the difference between the cost of our investments in the joint ventures and the book value of the underlying equity into income on a straight-line basis consistent with the lives of the underlying assets. The amortization of this difference was immaterial for the three and nine months ended September 30, 2018 and 2017 , respectively. (d) Capitalization of Costs Direct and indirect project costs that are clearly associated with the development of properties are capitalized as incurred. Project costs include all costs directly associated with the development of a property, including construction costs, interest, property taxes, insurance, legal fees and costs of personnel working on the project. Indirect costs that do not clearly relate to the projects under development are not capitalized and are charged to expense as incurred. Capitalization of costs begins when the activities necessary to get the development project ready for its intended use begins, which include costs incurred before the beginning of construction. Capitalization of costs ceases when the development project is substantially complete and ready for its intended use. Determining when a development project commences and when it is substantially complete and ready for its intended use involves a degree of judgment. We generally consider a development project to be substantially complete and ready for its intended use upon receipt of a certificate of occupancy. If and when development of a property is suspended pursuant to a formal change in the planned use of the property, we will evaluate whether the accumulated costs exceed the estimated value of the project and write off the amount of any such excess accumulated costs. For a development project that is suspended for reasons other than a formal change in the planned use of such property, the accumulated project costs are evaluated for impairment consistent with our impairment policies for long-lived assets. Capitalized costs are allocated to the specific components of a project that are benefited. During the three months ended September 30, 2018 and 2017 , we capitalized interest of approximately $9.7 million and $5.3 million , respectively. We capitalized interest of approximately $25.3 million and $13.7 million during the nine months ended September 30, 2018 and 2017 , respectively. We capitalized amounts relating to compensation and other overhead expense of employees direct and incremental to construction and successful leasing activities of approximately $19.5 million and $20.8 million during the three months ended September 30, 2018 and 2017 , respectively, and approximately $55.1 million and $58.4 million during the nine months ended September 30, 2018 and 2017 , respectively. In addition to capitalized cash compensation, approximately $6.4 million and $11.1 million of capitalized costs primarily related to external leasing commissions are included in improvements to and advances for investments in real estate in cash flows from investing activities in the condensed consolidated statements of cash flows for the nine months ended September 30, 2018 and 2017 , respectively. (e) Goodwill Goodwill represents the excess of the purchase price over the fair value of net tangible and intangible assets acquired and tangible and intangible liabilities assumed in a business combination. Goodwill is not amortized. We perform an annual impairment test for goodwill and between annual tests, we evaluate goodwill for impairment whenever events or changes in circumstances occur that would more likely than not reduce the fair value of a reporting unit below its carrying value. In our impairment tests of goodwill, we first assess qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying value. If based on this assessment, we determine that the fair value of the reporting unit is not less than its carrying value, then performing the additional two-step impairment test is unnecessary. If our qualitative assessment indicates that goodwill impairment is more likely than not, we perform a two-step impairment test. We test goodwill for impairment under the two-step impairment test by first comparing the book value of net assets including goodwill to the fair value of the reporting unit. If the fair value is determined to be less than the book value of the net assets, including goodwill, a second step is performed to compute the amount of impairment as the difference between the implied fair value of goodwill and its carrying value. We estimate the fair value of the reporting units using discounted cash flows. If the carrying value of goodwill exceeds its implied fair value, an impairment charge is recognized. We have not recognized any goodwill impairments since our inception. Since some of the goodwill is denominated in foreign currencies, changes to the goodwill balance occur over time due to changes in foreign exchange rates. The following is a summary of goodwill activity for the nine months ended September 30, 2018 (in thousands): Balance as of December 31, 2017 Impact of Change in Foreign Exchange Rates Balance as of September 30, 2018 Merger / Portfolio Acquisition Telx Acquisition $ 330,845 $ — $ 330,845 European Portfolio Acquisition 466,604 (16,253 ) 450,351 DuPont Fab ros Technology Merger 2,592,146 — 2,592,146 Total $ 3,389,595 $ (16,253 ) $ 3,373,342 (f) Share-Based Compensation The Company measures all share-based compensation awards at fair value on the date they are granted to employees and directors, and recognizes compensation cost, net of forfeitures, over the requisite service period for awards with only a service condition. The estimated fair value of the long-term incentive units and Class D units (discussed in Note 13) granted by us is being amortized on a straight-line basis over the expected service period. The fair value of share-based compensation awards that contain a market condition is measured using a Monte Carlo simulation method and not adjusted based on actual achievement of the market condition. (g) Assets and Liabilities Measured at Fair Value Fair value under U.S. GAAP is a market-based measurement, not an entity-specific measurement. Therefore, our fair value measurements are determined based on the assumptions that market participants would use in pricing the asset or liability. As a basis for considering market participant assumptions in fair-value measurements, we use a fair-value hierarchy that distinguishes between market participant assumptions based on market data obtained from sources independent of the reporting entity (observable inputs that are classified within Levels 1 and 2 of the hierarchy) and the reporting entity’s own assumptions about market participant assumptions (unobservable inputs classified within Level 3 of the hierarchy). Level 1 inputs utilize quoted prices (unadjusted) in active markets for identical assets or liabilities that the Company has the ability to access. Level 2 inputs are inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly or indirectly. Level 2 inputs may include quoted prices for similar assets and liabilities in active markets, as well as inputs that are observable for the asset or liability (other than quoted prices), such as interest rates, foreign exchange rates, and yield curves that are observable at commonly quoted intervals. Level 3 inputs are unobservable inputs for the asset or (h) Derivative Instruments Derivative financial instruments are employed to manage risks, including foreign currency and interest rate exposures and are not used for trading or speculative purposes. As part of the Company’s risk management program, a variety of financial instruments, such as interest rate swaps and foreign exchange contracts, may be used to mitigate interest rate exposure and foreign currency exposure. The Company recognizes all derivative instruments in the balance sheet at fair value. Changes in the fair value of derivatives are recognized periodically either in earnings or in stockholders’ equity as a component of accumulated other comprehensive income (loss), depending on whether the derivative financial instrument is undesignated or qualifies for hedge accounting, and if so, whether it represents a fair value, cash flow, or net investment hedge. Gains and losses on derivatives designated as cash flow hedges, to the extent they are included in the assessment of effectiveness, are recorded in other comprehensive income (loss) and subsequently reclassified to earnings to offset the impact of the hedged items when they occur. In the event it becomes probable the forecasted transaction to which a cash flow hedge relates will not occur, the derivative would be terminated and the amount in other comprehensive income (loss) would be recognized in earnings. Changes in the fair value of derivatives that are designated and qualify as a hedge of the net investment in foreign operations, to the extent they are included in the assessment of effectiveness, are reported in other comprehensive income (loss) and are deferred until disposal of the underlying assets. Gains and losses representing components excluded from the assessment of effectiveness for cash flow and fair value hedges are recognized in earnings on a straight-line basis in the same caption as the hedged item over the term of the hedge. Gains and losses representing components excluded from the assessment of effectiveness for net investment hedges are recognized in earnings on a straight-line basis over the term of the hedge. The net interest paid or received on interest rate swaps is recognized as interest expense. Gains and losses resulting from the early termination of interest rate swap agreements are deferred and amortized as adjustments to interest expense over the remaining period of the debt originally covered by the terminated swap. See Note 14 for further discussion on derivative instruments. (i) Income Taxes Digital Realty Trust, Inc. has elected to be treated as a real estate investment trust (a “REIT”) for federal income tax purposes. As a REIT, Digital Realty Trust, Inc. generally is not required to pay federal corporate income tax to the extent taxable income is currently distributed to its stockholders. If Digital Realty Trust, Inc. fails to qualify as a REIT in any taxable year, it will be subject to federal income tax (including any applicable alternative minimum tax for taxable years prior to 2018) on its taxable income. The Company is subject to foreign, state and local income taxes in the jurisdictions in which it conducts business. The Company’s taxable REIT subsidiaries are subject to federal, state and foreign income taxes to the extent there is taxable income. Accordingly, the Company recognizes current and deferred income taxes for its taxable REIT subsidiaries, including federal, state and non-U.S. jurisdictions, as appropriate. We assess our significant tax positions in accordance with U.S. GAAP for all open tax years and determine whether we have any material unrecognized liabilities from uncertain tax benefits. If a tax position is not considered “more-likely-than-not” to be sustained solely on its technical merits, no benefits of the tax position are to be recognized (for financial statement purposes). As of September 30, 2018 and December 31, 2017 , we had no assets or liabilities for uncertain tax positions. We classify interest and penalties from significant uncertain tax positions as interest expense and operating expense, respectively, in our condensed consolidated income statements. For the three and nine months ended September 30, 2018 and 2017 , we had no such interest or penalties. The tax year 2015 and thereafter remain open to examination by the major taxing jurisdictions with which the Company files tax returns. See Note 10 for further discussion on income taxes. (j) Presentation of Transactional-based Taxes We account for transactional-based taxes, such as value added tax, or VAT, for our international properties on a net basis. (k) Redeemable Noncontrolling Interests Redeemable noncontrolling interests include amounts related to partnership units issued by consolidated subsidiaries of the Company in which redemption for equity is outside the control of the Company. Partnership units which are determined to be contingently redeemable for cash under the Financial Accounting Standards Board’s "Distinguishing Liabilities from Equity" guidance are classified as redeemable noncontrolling interests and presented in the mezzanine section between total liabilities and stockholder’s equity on the Company’s condensed consolidated balance sheets. The amounts of consolidated net income attributable to the Company and to the noncontrolling interests are presented on the Company’s condensed consolidated income statements. (l) Revenue Recognition The majority of our revenue is derived from lease arrangements, which we account for in accordance with “Leases (Topic 840)”. We account for the non-lease components within our lease arrangements, as well as other sources of revenue, in accordance with “Revenue from Contracts with Customers (Topic 606)”. Revenue recognized as a result of applying Topic 840 was 97% and Topic 606 was 3% of total operating revenue for the three and nine months ended September 30, 2018 . Our leases are classified as operating leases and minimum rents are recognized on a straight-line basis over the terms of the leases, which may span multiple years. The excess of rents recognized over amounts contractually due pursuant to the underlying leases is included in deferred rent in the accompanying condensed consolidated balance sheets and contractually due but unpaid rents are included in accounts and other receivables. Tenant reimbursements for real estate taxes, common area maintenance, and other recoverable costs under our leases are recognized in the period that the expenses are incurred. Lease termination fees are recognized over the remaining term of the lease, effective as of the date the lease modification is finalized, assuming collection is not considered doubtful. As discussed above, we recognize amortization of the value of acquired above or below-market tenant leases as a reduction of rental revenue in the case of above-market leases or an increase to rental revenue in the case of below-market leases. Interconnection services are included in rental and other services on the condensed consolidated income statements and are generally provided on a month-to-month, one-year or multi-year term. Interconnection services include port and cross-connect services. Port services are typically sold on a one-year or multi-year term and revenue is recognized on a recurring monthly basis (straight-line). The Company bills customers on a monthly basis and recognizes the revenue over the period the service is provided. Revenue for cross-connect installations is generally recognized in the period the cross-connect is installed. Interconnection services that are not specific to a particular space are accounted for under Topic 606 and have terms that are generally one year or less. Occasionally, customers engage the Company for certain services. The nature of these services historically involves property management and construction management. The proper revenue recognition of these services can be different, depending on whether the arrangements are service revenue or contractor type revenue. Service revenues are typically recognized on an equal monthly basis based on the minimum fee to be earned. The monthly amounts could be adjusted depending on if certain performance milestones are met. Fee income arises primarily from contractual management agreements with entities in which we have a noncontrolling interest. The management fees are recognized as earned under the respective agreements. Management and other fee income related to partially owned noncontrolled entities are recognized to the extent attributable to the unaffiliated interest. We make subjective estimates as to when our revenue is earned and the collectability of our accounts receivable related to minimum rent, deferred rent, expense reimbursements, lease termination fees and other income. We specifically analyze accounts receivable and historical bad debts, customer concentrations, customer creditworthiness and current economic trends when evaluating the adequacy of the allowance for bad debts. These estimates have a direct impact on our net revenue because a higher bad debt allowance would result in lower net revenue, and recognizing rental revenue as earned in one period versus another would result in higher or lower net revenue for a particular period. (m) Transaction and Integration Expense Transaction and integration expense includes business combination expenses, other business development expenses and other expenses to integrate newly acquired investments, which are expensed as incurred. Transaction expenses include closing costs, broker commissions and other professional fees, including legal and accounting fees related to business combinations or acquisitions that were not consummated. Integration costs include transition costs associated with organizational restructuring (such as severance and retention payments and recruiting expenses), third-party consulting expenses directly related to the integration of acquired companies (in areas such as cost savings and synergy realization, technology and systems work), and internal costs such as training, travel and labor, reflecting time spent by Company personnel on integration activities and projects. Recurring costs are recorded in general and administrative expense. (n) Gains on Sale of Properties As of January 1, 2018, we began accounting for the sale of real estate properties under Financial Accounting Standards Board, or FASB, Accounting Standards Update, or ASU, No. 2017-05, Other Income—Gains and Losses from the Derecognition of Nonfinancial Assets (Subtopic 610-20), which provides for revenue recognition based on transfer of ownership. All properties were non-financial real estate assets and thus not businesses which were sold to noncustomers with no performance obligations subsequent to transfer of ownership. During the nine months ended September 30, 2018 , the Company sold real estate properties for gross proceeds of $291.7 million , and a recorded net gain of $80.4 million . (o) Management’s Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates made. On an on-going basis, we evaluate our estimates, including those related to the valuation of our real estate properties, tenant relationship value, goodwill, contingent consideration, accounts receivable and deferred rent receivable, performance-based equity compensation plans and the completeness of accrued liabilities. We base our estimates on historical experience, current market conditions, and various other assumptions that are believed to be reasonable under the circumstances. Actual results may vary from those estimates and those estimates could vary under different assumptions or conditions. (p) Segment and Geographic Information All of our properties generate similar revenues and expenses related to tenant rent and services and reimbursements and operating expenses. The sale and delivery of our products is consistent across all properties and although services are provided to a wide range of customers, the types of real estate services provided to them are standardized throughout the portfolio. As such, the properties in our portfolio have similar economic characteristics and the nature of the products and services provided to our customers and the method to distribute such services are consistent throughout the portfolio. In addition, the chief operating decision makers evaluate operating performance and make resource allocation decisions for the portfolio as a whole, rather than by property type or revenue stream. Consequently, our properties qualify for aggregation into one reporting segment. Operating revenues from properties in the United States were $629.3 million and $478.2 million and outside the United States were $139.7 million and $131.7 million for the three months ended September 30, 2018 and 2017 , respectively. Operating revenues from properties in the United States were $1.8 billion and $1.3 billion and outside the United States were $421.3 million and $380.0 million for the nine months ended September 30, 2018 and 2017 , respectively. We had investments in real estate located in the United States of $10.8 billion and $10.5 billion , and outside the United States of $3.3 billion and $3.1 billion , as of September 30, 2018 and December 31, 2017 , respectively. Operating revenues from properties located in the United Kingdom were $72.6 million and $70.1 million , or 9.4% and 11.5% of total operating revenues, for the three months ended September 30, 2018 and 2017 , respectively. Operating revenues from properties located in the United Kingdom were $221.9 million and $202.8 million , or 9.8% and 11.7% of total operating revenues, for the nine months ended September 30, 2018 and 2017 , respectively. No other foreign country comprised more than 10% of total operating revenues for each of these periods. We had investments in real estate located in the United Kingdom of $1.6 billion and $1.7 billion , or 11.6% and 12.1% of total long-lived assets, as of September 30, 2018 and December 31, 2017 , respectively. No other foreign country comprised more than 10% of total long-lived assets as of September 30, 2018 and December 31, 2017 . (q) New Accounting Pronouncements New Accounting Standards Adopted In August 2017, the FASB issued ASU No. 2017-12, "Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities". The new standard amends the hedge accounting recognition and presentation requirements in Accounting Standards Codification, or ASC, 815. As permitted by ASU No. 2017-12, the Company early adopted this standard in the first quarter of 2018 on a prospective basis. Refer to Note 2(h), Derivative Instruments, for our policy related to the adoption of this standard. In January 2016, the FASB issued ASU No. 2016-01, "Recognition and Measurement of Financial Assets and Financial Liabilities". The guidance requires entities to measure equity investments that do not result in consolidation and are not accounted for under the equity method at fair value and to record changes in instruments specific credit risk for financial liabilities measured under the fair value option in other comprehensive income. The principal effect of ASU No. 2016-01 on our condensed consolidated financial statements is that, prior to adoption of ASU No. 2016-01, changes in the fair values of investments in equity securities with readily determinable fair values or redemption values were recognized in other comprehensive income until realized, while under ASU No. 2016-01 all changes in the fair values of these equity securities are recognized in current earnings. The update is effective for fiscal years beginning after December 15, 2017, and for interim periods therein. We adopted this standard in the first quarter of 2018 and the adoption did not have a material impact on our condensed consolidated financial statements. In May 2014, the FASB issued ASU No. 2014-09, "Revenue from Contracts with Customers (Topic 606)", and since that date has issued several additional ASUs intended to clarify certain aspects of ASU No. 2014-09 and to provide for certain practical expedients entities may elect upon adoption. Collectively, these ASUs outline a single comprehensive model for entities to use in accounting for revenues arising from contracts with customers. We adopted Topic 606 in the first quarter of 2018 using the modified retrospective transition method and applied Topic 606 to those contracts that were not completed as of January 1, 2018. The results for reporting periods beginning after January 1, 2018 are presented under Topic 606, while prior period amounts are not adjusted and continue to be presented under Topic 605. Our financial statements did not recognize a material effect from the cumulative impact of adopting Topic 606 as the new accounting standard does not impact lessor accounting. Refer to Note 2(l), Revenue Recognition, for the updated policy related to the adoption of this standard. New Accounting Standards Issued but not yet Adopted In February 2016, the FASB issued ASU No. 2016-02, "Leases (Topic 842)", which s

Investments in Real Estate

Investments in Real Estate	9 Months Ended
	Sep. 30, 2018
Real Estate [Abstract]
Investments In Real Estate	Investments in Real Estate Acquisitions We acquired the following real estate during the nine months ended September 30, 2018 : Location Market Date Acquired Amount (in millions) 10000-10006 Godwin Drive (1) Northern Virginia May 3, 2018 $ 16.5 2825-2845 Lafayette Street Silicon Valley Jun 19, 2018 55.5 9905 Godwin Drive (1) Northern Virginia Jul 11, 2018 5.8 Pacific Boulevard and S. Sterling Boulevard Northern Virginia Jul 17, 2018 26.8 160 Lockwood Road (1)(2) Sydney Sep 7, 2018 7.7 $ 112.3 (1) Represents currently vacant land which is not included in our operating property count. Purchase price excludes capitalized closing costs. (2) Purchase price in U.S. dollars. Held for Sale We sold the remaining four properties that met the criteria to be classified as held for sale as of March 31, 2018 during the three months ended June 30, 2018. As of December 31, 2017 , we had identified eight properties that met the criteria to be classified as held for sale. As of December 31, 2017 , the eight properties had an aggregate carrying value of $139.5 million within total assets and $5.0 million within total liabilities and are shown as assets held for sale and obligations associated with assets held for sale on the consolidated balance sheet, respectively. The properties are not representative of a significant component of our portfolio, nor do the potential sales represent a significant shift in our strategy. Dispositions We sold the following real estate properties during the nine months ended September 30, 2018 : Location Metro Area Date Sold Gross Proceeds (in millions) Gain (loss) on sale (in millions) 200 Quannapowitt Parkway Boston Jan 25, 2018 $ 15.0 $ (0.4 ) 34551 Ardenwood Boulevard Silicon Valley Feb 9, 2018 73.3 25.3 3065 Gold Camp Drive Sacramento Mar 14, 2018 14.2 5.4 11085 Sun Center Drive Sacramento Mar 14, 2018 36.8 9.1 Austin Portfolio Austin Apr 19, 2018 47.6 12.0 2010 East Centennial Circle Phoenix May 22, 2018 5.5 (0.5 ) 1125 Energy Park Drive Minneapolis May 31, 2018 7.0 2.8 360 Spear Street San Francisco Sep 21, 2018 92.3 26.7 $ 291.7 $ 80.4

Investments in Unconsolidated J

Investments in Unconsolidated Joint Ventures	9 Months Ended
	Sep. 30, 2018
Equity Method Investments and Joint Ventures [Abstract]
Investments in Unconsolidated Joint Ventures	Investments in Unconsolidated Joint Ventures As of September 30, 2018 , our investments in unconsolidated joint ventures consist of effective 50% interests in four joint ventures that own data center buildings in Seattle, Hong Kong, Tokyo and Osaka, 20% interests in two joint ventures, one of which owns 10 data center properties with an investment fund managed by Prudential Real Estate Investors (PREI ® ) and the other which owns one data center property with an affiliate of Griffin Capital Essential Asset REIT, Inc. (GCEAR), and a 17% interest in a joint venture that owns a data center property in Silicon Valley. The Osaka/Tokyo joint venture was formed on November 1, 2017. The following tables present summarized financial information for our material joint ventures as of September 30, 2018 and December 31, 2017 and for the nine months ended September 30, 2018 and 2017 (in thousands): As of September 30, 2018 Nine Months Ended September 30, 2018 2018 Net Investment in Properties Total Assets Debt Total Liabilities Equity Revenues Property Operating Expense Net Operating Income Net Income Total Unconsolidated Joint Ventures $ 1,045,943 $ 1,338,295 $ 719,801 $ 847,814 $ 490,481 $ 159,336 $ (56,603 ) $ 102,733 $ 31,193 Our investment in and share of equity in earnings of unconsolidated joint ventures $ 169,919 $ 23,734 As of December 31, 2017 Nine Months Ended September 30, 2017 2017 Net Investment in Properties Total Assets Debt Total Liabilities Equity Revenues Property Operating Expense Net Operating Income Net Income Total Unconsolidated Joint Ventures $ 1,061,950 $ 1,375,006 $ 712,690 $ 869,879 $ 505,127 $ 106,793 $ (32,869 ) $ 73,924 $ 32,545 Our investment in and share of equity in earnings of unconsolidated joint ventures $ 163,477 $ 19,592 The amounts reflected in the tables above, except for our investment in and share of equity in earnings of unconsolidated joint ventures, are based on the historical financial information of the individual joint ventures. The debt of our unconsolidated joint ventures generally are non-recourse to us, except for customary exceptions pertaining to such matters as intentional misuse of funds, environmental conditions, and material misrepresentations. Differences between the Company’s investment in the joint ventures and the amount of the underlying equity in net assets of the joint ventures are due to basis differences resulting from the Company’s equity investment recorded at its historical basis versus the fair value of the Company’s contributed interest in the joint ventures. Our proportionate share of the earnings or losses related to these unconsolidated joint ventures is reflected as equity in earnings of unconsolidated joint ventures on the accompanying condensed consolidated income statements.

Acquired Intangible Assets and

Acquired Intangible Assets and Liabilities	9 Months Ended
	Sep. 30, 2018
Acquired Intangible Assets And Liabilities [Abstract]
Acquired Intangible Assets and Liabilities	Acquired Intangible Assets and Liabilities The following summarizes our acquired intangible assets (real estate intangibles, comprised of acquired in-place lease value and tenant relationship value along with acquired above-market lease value) and intangible liabilities (acquired below-market lease value) as of September 30, 2018 and December 31, 2017 . Balance as of (Amounts in thousands) September 30, 2018 December 31, 2017 Real Estate Intangibles: Acquired in-place lease value: Gross amount $ 1,452,050 $ 1,473,515 Accumulated amortization (748,087 ) (613,948 ) Net $ 703,963 $ 859,567 Tenant relationship value: Gross amount $ 1,969,111 $ 1,978,277 Accumulated amortization (261,618 ) (169,919 ) Net $ 1,707,493 $ 1,808,358 Acquired above-market leases: Gross amount $ 280,399 $ 294,514 Accumulated amortization (145,272 ) (110,139 ) Net $ 135,127 $ 184,375 Acquired below-market leases: Gross amount $ 443,457 $ 469,119 Accumulated amortization (235,255 ) (219,654 ) Net $ 208,202 $ 249,465 Amortization of acquired below-market leases, net of acquired above-market leases, resulted in a (decrease)/increase in rental revenues of $(6.8) million and $0.7 million for the three months ended September 30, 2018 and 2017 , respectively, and $(20.6) million and $4.7 million for the nine months ended September 30, 2018 and 2017 , respectively. The expected average remaining lives for acquired below-market leases and acquired above-market leases is 8.3 years and 3.0 years, respectively, as of September 30, 2018 . Estimated annual amortization of acquired below-market leases, net of acquired above-market leases, for each of the five succeeding years and thereafter, commencing October 1, 2018 is as follows: (Amounts in thousands) Remainder of 2018 $ (6,690 ) 2019 (16,127 ) 2020 (3,902 ) 2021 899 2022 7,932 Thereafter 90,963 Total $ 73,075 Amortization of acquired in-place lease value (a component of depreciation and amortization expense) was $50.2 million and $20.1 million for the three months ended September 30, 2018 and 2017 , respectively, and $162.3 million and $48.7 million for the nine months ended September 30, 2018 and 2017 , respectively. The expected average amortization period for acquired in-place lease value is 6.2 years as of September 30, 2018 . The weighted average remaining contractual life for acquired leases excluding renewals or extensions is 5.7 years as of September 30, 2018 . Estimated annual amortization of acquired in-place lease value for each of the five succeeding years and thereafter, commencing October 1, 2018 is as follows: (Amounts in thousands) Remainder of 2018 $ 47,782 2019 147,470 2020 111,611 2021 87,059 2022 65,179 Thereafter 244,862 Total $ 703,963 Amortization of tenant relationship value (a component of depreciation and amortization expense) was approximately $30.8 million and $19.9 million for the three months ended September 30, 2018 and 2017 , respectively, and $92.8 million and $55.0 million for the nine months ended September 30, 2018 and 2017 , respectively. As of September 30, 2018 , the weighted average remaining contractual life for tenant relationship value was 14.5 years. Estimated annual amortization of tenant relationship value for each of the five succeeding years and thereafter, commencing October 1, 2018 is as follows: (Amounts in thousands) Remainder of 2018 $ 30,808 2019 123,232 2020 123,232 2021 123,232 2022 123,232 Thereafter 1,183,757 Total $ 1,707,493

Debt of the Company

Debt of the Company	9 Months Ended
	Sep. 30, 2018
Debt Disclosure [Abstract]
Debt of the Company	Debt of the Company In this Note 6, the “Company” refers only to Digital Realty Trust, Inc. and not to any of its subsidiaries. The Company itself does not currently have any indebtedness. All debt is currently held directly or indirectly by the Operating Partnership. Guarantee of Debt The Company guarantees the Operating Partnership’s obligations with respect to its 5.875% notes due 2020 ( 5.875% 2020 Notes ), 3.400% notes due 2020 ( 3.400% 2020 Notes), 5.250% notes due 2021 ( 2021 Notes ), 3.950% notes due 2022 ( 3.950% 2022 Notes ), 3.625% notes due 2022 ( 3.625% 2022 Notes ), 2.750% notes due 2023 (2.750% 2023 Notes), 4.750% notes due 2025 ( 4.750% 2025 Notes), 3.700% notes due 2027 (2027 Notes) and 4.450% notes due 2028 (2028 Notes). The Company and the Operating Partnership guarantee the obligations of Digital Stout Holding, LLC, a wholly owned subsidiary of the Operating Partnership, with respect to its 4.750% notes due 2023 (4.750% 2023 Notes ), 2.750% notes due 2024 (2.750% 2024 Notes), 4.250% notes due 2025 ( 4.250% 2025 Notes ) and 3.300% notes due 2029 (2029 Notes) and the obligations of Digital Euro Finco, LLC, an indirect wholly owned subsidiary of the Operating Partnership, with respect to its 2.625% notes due 2024 (2.625% 2024 Notes) and Floating Rate Guaranteed Notes due 2019 (2019 Notes). The Company is also the guarantor of the Operating Partnership’s and its subsidiary borrowers’ obligations under the global revolving credit facility and unsecured term loans.

Debt of the Operating Partnersh

Debt of the Operating Partnership	9 Months Ended
	Sep. 30, 2018
Digital Realty Trust, L.P.
Debt Instrument [Line Items]
Debt of the Operating Partnership	Debt of the Operating Partnership A summary of outstanding indebtedness of the Operating Partnership as of September 30, 2018 and December 31, 2017 is as follows (in thousands): Indebtedness Interest Rate at September 30, 2018 Maturity Date Principal Outstanding at September 30, 2018 Principal Outstanding at December 31, 2017 Global revolving credit facility Various (1) Jan 15, 2020 $ 594,983 (2) $ 558,191 (2) Deferred financing costs, net (4,694 ) (7,245 ) Global revolving credit facility, net 590,289 550,946 Unsecured Term Loans Unsecured term loan — 5-year Various (3)(4) Jan 15, 2021 1,056,702 (5) 1,125,117 (5) Unsecured term loan — 7-year Various (3)(4) Jan 15, 2023 300,000 (5) 300,000 (5) Deferred financing costs, net (3,733 ) (4,784 ) Unsecured term loan, net 1,352,969 1,420,333 Floating rate notes due 2019 EURIBOR + 0.500% May 22, 2019 145,050 (6) 150,063 (6) 5.875% notes due 2020 5.875% Feb 1, 2020 500,000 500,000 3.400% notes due 2020 3.400% Oct 1, 2020 500,000 500,000 5.250% notes due 2021 5.250% Mar 15, 2021 400,000 400,000 3.950% notes due 2022 3.950% Jul 1, 2022 500,000 500,000 3.625% notes due 2022 3.625% Oct 1, 2022 300,000 300,000 2.750% notes due 2023 2.750% Feb 1, 2023 350,000 350,000 4.750% notes due 2023 4.750% Oct 13, 2023 390,930 (7) 405,390 (7) 2.625% notes due 2024 2.625% Apr 15, 2024 696,240 (6) 720,300 (6) 2.750% notes due 2024 2.750% Jul 19, 2024 325,775 (7) 337,825 (7) 4.250% notes due 2025 4.250% Jan 17, 2025 521,240 (7) 540,520 (7) 4.750% notes due 2025 4.750% Oct 1, 2025 450,000 450,000 3.700% notes due 2027 3.700% Aug 15, 2027 1,000,000 1,000,000 4.450% notes due 2028 4.450% Jul 15, 2028 650,000 — 3.300% notes due 2029 3.300% Jul 19, 2029 456,085 (7) 472,955 (7) Unamortized discounts (16,495 ) (18,508 ) Total senior notes, net of discount 7,168,825 6,608,545 Deferred financing costs, net (38,284 ) (37,788 ) Total unsecured senior notes, net of discount and deferred financing costs 7,130,541 6,570,757 Indebtedness Interest Rate at September 30, 2018 Maturity Date Principal Outstanding September 30, 2018 Principal Outstanding December 31, 2017 Mortgage loans: 731 East Trade Street 8.22% Jul 1, 2020 $ 1,930 $ 2,370 Secured note due 2023 LIBOR + 1.100% (4) Mar 1, 2023 104,000 104,000 Unamortized net premiums 171 241 Total mortgage loans, including premiums 106,101 106,611 Deferred financing costs, net (29 ) (29 ) Total mortgage loans, including premiums and net of deferred financing costs 106,072 106,582 Total indebtedness $ 9,179,871 $ 8,648,618 _________________________________ (1) The interest rate for borrowings under the global revolving credit facility equals the applicable index plus a margin of 100 basis points, which is based on the current credit ratings of our long-term debt. An annual facility fee of 20 basis points, which is based on the credit ratings of our long-term debt, is due and payable quarterly on the total commitment amount of the facility. Two six -month extensions are available, which we may exercise if certain conditions are met. (2) Balances as of September 30, 2018 and December 31, 2017 are as follows (balances, in thousands): Denomination of Draw Balance as of September 30, 2018 Weighted-average interest rate Balance as of December 31, 2017 Weighted-average interest rate Floating Rate Borrowing (a) U.S. dollar ($) $ 240,000 3.23 % $ 400,000 2.48 % British pound sterling (£) — — % 18,918 (d) 1.50 % Euro (€) 74,846 (c) 0.62 % 31,213 (d) 0.62 % Australian dollar (AUD) 58,659 (c) 2.85 % — — % Hong Kong dollar (HKD) 7,779 (c) 2.91 % 4,100 (d) 2.20 % Japanese yen (JPY) 116,195 (c) 0.90 % 65,890 (d) 0.96 % Singapore dollar (SGD) 25,114 (c) 2.61 % — — % Canadian dollar (CAD) 67,390 (c) 2.82 % 23,070 (d) 2.36 % Total $ 589,983 2.32 % $ 543,191 2.15 % Base Rate Borrowing (b) U.S. dollar ($) $ 5,000 5.25 % $ 15,000 4.50 % Total borrowings $ 594,983 2.35 % $ 558,191 2.21 % (a) The interest rates for floating rate borrowings under the global revolving credit facility equal the applicable index plus a margin of 100 basis points, which is based on the credit ratings of our long-term debt. (b) The interest rates for base rate borrowings under the global revolving credit facility equal the U.S. Prime Rate. (c) Based on exchange rates of $1.16 to €1.00, $0.72 to 1.00 AUD, $0.13 to 1.00 HKD, $0.01 to 1.00 JPY, $0.73 to 1.00 SGD and $0.77 to 1.00 CAD, respectively, as of September 30, 2018 . (d) Based on exchange rates of $1.35 to £1.00, $1.20 to €1.00, $0.13 to 1.00 HKD, $0.01 to 1.00 JPY and $0.80 to 1.00 CAD, respectively, as of December 31, 2017 . (3) Interest rates are based on our current senior unsecured debt ratings and are 110 basis points and 155 basis points over the applicable index for floating rate advances for the 5 -Year Term Loan and the 7 -Year Term Loan, respectively. (4) We have entered into interest rate swap agreements as a cash flow hedge for interest generated by the U.S. dollar, British pound sterling and Canadian dollar tranches of the unsecured term loans and the secured note due 2023. See Note 14 "Derivative Instruments" for further information. (5) Balances as of September 30, 2018 and December 31, 2017 are as follows (balances, in thousands): Denomination of Draw Balance as of September 30, 2018 Weighted-average interest rate Balance as of December 31, 2017 Weighted-average interest rate U.S. dollar ($) $ 606,911 3.47 % (b) $ 606,911 2.78 % (d) British pound sterling (£) 220,843 (a) 1.82 % (b) 229,011 (c) 1.59 % (d) Singapore dollar (SGD) 189,713 (a) 2.68 % 233,788 (c) 2.17 % Australian dollar (AUD) 166,369 (a) 2.94 % 179,841 (c) 2.79 % Hong Kong dollar (HKD) 85,221 (a) 2.80 % 85,762 (c) 2.20 % Canadian dollar (CAD) 76,298 (a) 2.93 % (b) 78,357 (c) 2.44 % (d) Japanese yen (JPY) 11,347 (a) 1.01 % 11,447 (c) 1.05 % Total $ 1,356,702 2.94 % (b) $ 1,425,117 2.42 % (d) (a) Based on exchange rates of $1.30 to £1.00, $0.73 to 1.00 SGD, $0.72 to 1.00 AUD, $0.13 to 1.00 HKD, $0.77 to 1.00 CAD and $0.01 to 1.00 JPY, respectively, as of September 30, 2018 . (b) As of September 30, 2018 , the weighted-average interest rate reflecting interest rate swaps was 2.72% (U.S. dollar), 1.89% (British pound sterling), 1.88% (Canadian dollar) and 2.55% (Total). See Note 14 "Derivative Instruments" for further discussion on interest rate swaps. (c) Based on exchange rates of $1.35 to £1.00, $0.75 to 1.00 SGD, $0.78 to 1.00 AUD, $0.13 to 1.00 HKD, $0.80 to 1.00 CAD and $0.01 to 1.00 JPY, respectively, as of December 31, 2017 . (d) As of December 31, 2017 , the weighted-average interest rate reflecting interest rate swaps was 2.72% (U.S. dollar), 1.89% (British pound sterling), 1.88% (Canadian dollar) and 2.41% (Total). (6) Based on exchange rates of $1.16 to €1.00 as of September 30, 2018 and $1.20 to €1.00 as of December 31, 2017 . (7) Based on exchange rates of $1.30 to £1.00 as of September 30, 2018 and $1.35 to £1.00 as of December 31, 2017 . Global Revolving Credit Facility On January 15, 2016, we refinanced our global revolving credit facility and entered into a global senior credit agreement for a $2.0 billion senior unsecured revolving credit facility, which we refer to as the global revolving credit facility, that replaced the $2.0 billion revolving credit facility executed on August 15, 2013, as amended. The global revolving credit facility has an accordion feature that enables us to increase the borrowing capacity of the credit facility to up to $2.5 billion , subject to the receipt of lender commitments and other conditions precedent. The refinanced facility matures on January 15, 2020 , with two six -month extension options available. The interest rate for borrowings under the global revolving credit facility equals the applicable index plus a margin which is based on the credit ratings of our long-term debt and is currently 100 basis points. An annual facility fee on the total commitment amount of the facility, based on the credit ratings of our long-term debt, currently 20 basis points, is payable quarterly. Funds may be drawn in U.S., Canadian, Singapore, Australian and Hong Kong dollars, as well as Euro, British pound sterling and Japanese yen. As of September 30, 2018 , interest rates are based on 1-month LIBOR, 1-month EURIBOR, 1-month BBR, 1-month HIBOR, 1-month JPY LIBOR, 1-month SOR and 1-month CDOR, plus a margin of 1.00% . We have used and intend to use available borrowings under the global revolving credit facility to acquire additional properties, fund development opportunities and for general working capital and other corporate purposes, including potentially for the repurchase, redemption or retirement of outstanding debt or equity securities. As of September 30, 2018 , approximately $44.6 million of letters of credit were issued. The global revolving credit facility contains various restrictive covenants, including limitations on our ability to incur additional indebtedness, make certain investments or merge with another company, and requirements to maintain financial coverage ratios, including with respect to unencumbered assets. In addition, the global revolving credit facility restricts Digital Realty Trust, Inc. from making distributions to its stockholders, or redeeming or otherwise repurchasing shares of its capital stock, after the occurrence and during the continuance of an event of default, except in limited circumstances including as necessary to enable Digital Realty Trust, Inc. to maintain its qualification as a REIT and to minimize the payment of income or excise tax. As of September 30, 2018 , we were in compliance with all of such covenants. Unsecured Term Loans On January 15, 2016, we refinanced our senior unsecured multi-currency term loan facility and entered into a term loan agreement, which governs (i) a $1.25 billion 5 -year senior unsecured term loan, which we refer to as the 5 -Year Term Loan, and (ii) a $300 million 7 -year senior unsecured term loan, which we refer to as the 7 -Year Term Loan. The 2016 term loan agreement replaced the $1.0 billion term loan agreement executed on April 16, 2012, as amended. The 5 -Year Term Loan matures on January 15, 2021 and the 7 -Year Term Loan matures on January 15, 2023 . In addition, we have the ability from time to time to increase the aggregate size of lending under the 2016 term loan agreement from $1.55 billion to up to $1.8 billion , subject to receipt of lender commitments and other conditions precedent. Interest rates are based on our senior unsecured debt ratings and are currently 110 basis points and 155 basis points over the applicable index for floating rate advances for the 5 -Year Term Loan and the 7 -Year Term Loan, respectively. Funds may be drawn in U.S., Canadian, Singapore, Australian and Hong Kong dollars, as well as Euro, British pound sterling and Japanese yen. Based on exchange rates in effect at September 30, 2018 , the balance outstanding is approximately $1.4 billion , excluding deferred financing costs. We have used borrowings under the term loans for acquisitions, repayment of indebtedness, development, working capital and general corporate purposes. The covenants under the term loans are consistent with our global revolving credit facility and, as of September 30, 2018 , we were in compliance with all of such covenants. 3.750% Notes due 2030 On October 17, 2018, Digital Stout Holding, LLC, a wholly owned subsidiary of Digital Realty Trust, L.P., issued and sold £400.0 million (approximately $524.6 million based on the exchange rate on October 17, 2018) aggregate principal amount of 3.750% Guaranteed Notes due 2030, or the 2030 Notes. The 2030 Notes are senior unsecured obligations of Digital Stout Holding, LLC and are fully and unconditionally guaranteed by Digital Realty Trust, Inc. and Digital Realty Trust, L.P. Net proceeds from the offering were approximately £393.5 million (approximately $516.1 million based on the exchange rate on October 17, 2018) after deducting managers’ discounts and estimated offering expenses. We intend to use the net proceeds from the offering of the 2030 Notes to repay borrowings outstanding under the operating partnership’s global credit facilities, acquire additional properties or businesses, fund development opportunities, and to provide for working capital and other general corporate purposes, including potentially for the repayment of other debt or the repurchase, redemption, or retirement of outstanding debt securities, or a combination of the foregoing. The indenture governing the 2030 Notes contains certain covenants, including (1) a leverage ratio not to exceed 60% , (2) a secured debt leverage ratio not to exceed 40% and (3) an interest coverage ratio of greater than 1.50 , and also requires us to maintain total unencumbered assets of not less than 150% of the aggregate principal amount of unsecured debt. The table below summarizes our debt maturities and principal payments as of September 30, 2018 (in thousands): Global Revolving Credit Facility (1) Unsecured Unsecured Senior Notes Mortgage Loans Total Debt Remainder of 2018 $ — $ — $ — $ 153 $ 153 2019 — — 145,050 644 145,694 2020 594,983 — 1,000,000 1,133 1,596,116 2021 — 1,056,702 400,000 — 1,456,702 2022 — — 800,000 — 800,000 Thereafter — 300,000 4,840,270 104,000 5,244,270 Subtotal $ 594,983 $ 1,356,702 $ 7,185,320 $ 105,930 $ 9,242,935 Unamortized discount — — (16,495 ) — (16,495 ) Unamortized premium — — — 171 171 Total $ 594,983 $ 1,356,702 $ 7,168,825 $ 106,101 $ 9,226,611 (1) Subject to two six -month extension options exercisable by us. The bank group is obligated to grant the extension options provided we give proper notice, we make certain representations and warranties and no default exists under the global revolving credit facility.

Income per Share

Income per Share	9 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Income per Share	Income per Share The following is a summary of basic and diluted income per share (in thousands, except share and per share amounts): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Net income (loss) available to common stockholders $ 67,268 $ (4,140 ) $ 218,700 $ 119,842 Weighted average shares outstanding—basic 206,118,472 170,194,254 205,931,031 163,481,306 Potentially dilutive common shares: Unvested incentive units 169,100 — 160,117 150,369 Forward equity offering 37,884 — 1,847 166,493 Market performance-based awards 440,800 — 462,632 572,928 Weighted average shares outstanding—diluted 206,766,256 170,194,254 206,555,627 164,371,096 Income (loss) per share: Basic $ 0.33 $ (0.02 ) $ 1.06 $ 0.73 Diluted $ 0.33 $ (0.02 ) $ 1.06 $ 0.73 We have excluded the following potentially dilutive securities in the calculations above as they would be antidilutive or not dilutive: Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Weighted average of Operating Partnership common units not owned by Digital Realty Trust, Inc. 8,170,912 3,266,451 8,268,382 2,566,766 Potentially dilutive Series C Cumulative Redeemable Perpetual Preferred Stock 1,727,724 329,709 1,864,489 109,903 Potentially dilutive Series F Cumulative Redeemable Preferred Stock — — — 617,734 Potentially dilutive Series G Cumulative Redeemable Preferred Stock 2,142,282 2,193,331 2,311,864 2,262,875 Potentially dilutive Series H Cumulative Redeemable Preferred Stock 3,139,291 3,214,098 3,387,795 3,316,008 Potentially dilutive Series I Cumulative Redeemable Preferred Stock 2,144,789 2,195,898 2,314,569 2,265,524 Potentially dilutive Series J Cumulative Redeemable Preferred Stock 1,711,186 1,045,730 1,846,643 348,577 Total 19,036,184 12,245,217 19,993,742 11,487,387

Income per Unit

Income per Unit	9 Months Ended
	Sep. 30, 2018
Digital Realty Trust, L.P.
Class of Stock [Line Items]
Income per Unit	Income per Unit The following is a summary of basic and diluted income per unit (in thousands, except unit and per unit amounts): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Net income (loss) available to common unitholders $ 69,968 $ (4,219 ) $ 227,580 $ 121,474 Weighted average units outstanding—basic 214,289,384 173,460,704 214,199,414 166,048,072 Potentially dilutive common units: Unvested incentive units 169,100 — 160,117 166,493 Forward equity offering 37,884 — 1,847 150,369 Market performance-based awards 440,800 — 462,632 572,928 Weighted average units outstanding—diluted 214,937,168 173,460,704 214,824,010 166,937,862 Income (loss) per unit: Basic $ 0.33 $ (0.02 ) $ 1.06 $ 0.73 Diluted $ 0.33 $ (0.02 ) $ 1.06 $ 0.73 We have excluded the following potentially dilutive securities in the calculations above as they would be antidilutive or not dilutive: Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Potentially dilutive Series C Cumulative Redeemable Perpetual Preferred Units 1,727,724 329,709 1,864,489 109,903 Potentially dilutive Series F Cumulative Redeemable Preferred Units — — — 617,734 Potentially dilutive Series G Cumulative Redeemable Preferred Units 2,142,282 2,193,331 2,311,864 2,262,875 Potentially dilutive Series H Cumulative Redeemable Preferred Units 3,139,291 3,214,098 3,387,795 3,316,008 Potentially dilutive Series I Cumulative Redeemable Preferred Units 2,144,789 2,195,898 2,314,569 2,265,524 Potentially dilutive Series J Cumulative Redeemable Preferred Units 1,711,186 1,045,730 1,846,643 348,577 Total 10,865,272 8,978,766 11,725,360 8,920,621

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Digital Realty Trust, Inc. has elected to be treated and believes that it has been organized and has operated in a manner that has enabled it to qualify as a REIT for federal income tax purposes. As a REIT, Digital Realty Trust, Inc. is generally not subject to corporate level federal income taxes on taxable income distributed currently to its stockholders. Since inception, Digital Realty Trust, Inc. has distributed at least 100% of its taxable income annually and intends to do so for the tax year ending December 31, 2018 . As such, no provision for federal income taxes has been included in the Company's accompanying condensed consolidated financial statements for the three and nine months ended September 30, 2018 and 2017 . The Operating Partnership is a partnership and is not required to pay federal income tax. Instead, taxable income is allocated to its partners, who include such amounts on their federal income tax returns. As such, no provision for federal income taxes has been included in the Operating Partnership’s accompanying condensed consolidated financial statements. We have elected taxable REIT subsidiary (“TRS”) status for some of our consolidated subsidiaries. In general, a TRS may provide services that would otherwise be considered impermissible for REITs to provide and may hold assets that REITs cannot hold directly. Income taxes for TRS entities were accrued, as necessary, for the three and nine months ended September 30, 2018 and 2017 . For our TRS entities and foreign subsidiaries that are subject to U.S. federal, state and foreign income taxes, deferred tax assets and liabilities are established for temporary differences between the financial reporting basis and the tax basis of assets and liabilities at the enacted tax rates expected to be in effect when the temporary differences reverse. A valuation allowance for deferred tax assets is provided if we believe it is more likely than not that the deferred tax asset may not be realized, based on available evidence at the time the determination is made. An increase or decrease in the valuation allowance that results from the change in circumstances that causes a change in our judgment about the realizability of the related deferred tax asset is included in the income statement. Deferred tax assets (net of valuation allowance) and liabilities for our TRS entities and foreign subsidiaries were accrued, as necessary, for the three and nine months ended September 30, 2018 and 2017 . As of September 30, 2018 and December 31, 2017 , we had deferred tax liabilities net of deferred tax assets of approximately $158.3 million and $167.0 million , respectively, primarily related to our foreign properties, classified in accounts payable and other accrued expenses in the condensed consolidated balance sheet. The majority of our net deferred tax liability relates to differences between tax basis and book basis of the assets acquired in the Sentrum portfolio acquisition during 2012 and the European portfolio acquisition in July 2016. The valuation allowance against the deferred tax assets at September 30, 2018 and December 31, 2017 relate primarily to net operating loss carryforwards attributable to certain foreign jurisdictions and from the acquisition of Telx, that we do not expect to utilize, and deferred tax assets resulting from certain foreign real estate acquisition costs, which are not depreciated for tax purposes, but are deductible upon ultimate sale of the property. Given the indefinite holding period associated with these assets, realization of these deferred tax assets is not more-likely-than-not as of September 30, 2018 and December 31, 2017 . The federal tax legislation enacted on December 22, 2017, commonly known as the Tax Cuts and Jobs Act (the “2017 Tax Legislation”), reduced the corporate federal tax rate in the U.S. to 21%, effective upon January 1, 2018. As such, deferred tax assets and liabilities are remeasured using the lower corporate federal tax rate at December 31, 2017 . While we do not expect other material impacts, the new tax rules are complex and lack developed administrative guidance. We continue to work with our tax advisors to analyze and determine the full impact that the 2017 Tax Legislation as a whole will have on us.

Equity and Accumulated Other Co

Equity and Accumulated Other Comprehensive Loss, Net	9 Months Ended
	Sep. 30, 2018
Equity [Abstract]
Equity and Accumulated Other Comprehensive Loss, Net	Equity and Accumulated Other Comprehensive Loss, Net (a) Forward Equity Sale On September 27, 2018, Digital Realty Trust, Inc. completed an underwritten public offering of 9,775,000 shares of its common stock (including 1,275,000 shares from the exercise in full of the underwriters' option to purchase additional shares), all of which were offered in connection with forward sale agreements it entered into with certain financial institutions acting as forward purchasers. The forward purchasers borrowed and sold an aggregate of 9,775,000 shares of Digital Realty Trust, Inc.’s common stock in the public offering. Digital Realty Trust, Inc. did not receive any proceeds from the sale of our common stock by the forward purchasers in the public offering. The Company expects to receive net proceeds of approximately $1.1 billion (net of fees and estimated expenses) upon full physical settlement of the forward sale agreements, which is anticipated to be no later than September 27, 2019. (b) Noncontrolling Interests in Operating Partnership Noncontrolling interests in the Operating Partnership relate to the interests that are not owned by Digital Realty Trust, Inc. The following table shows the ownership interests in the Operating Partnership as of September 30, 2018 and December 31, 2017 : September 30, 2018 December 31, 2017 Number of units Percentage of total Number of units Percentage of total Digital Realty Trust, Inc. 206,267,055 96.1 % 205,470,300 96.0 % Noncontrolling interests consist of: Common units held by third parties 6,411,484 3.0 % 6,899,094 3.2 % Incentive units held by employees and directors (see Note 14) 1,929,103 0.9 % 1,590,001 0.8 % 214,607,642 100.0 % 213,959,395 100.0 % Limited partners have the right to require the Operating Partnership to redeem part or all of their common units for cash based on the fair market value of an equivalent number of shares of Digital Realty Trust, Inc. common stock at the time of redemption. Alternatively, Digital Realty Trust, Inc. may elect to acquire those common units in exchange for shares of Digital Realty Trust, Inc. common stock on a one -for-one basis, subject to adjustment in the event of stock splits, stock dividends, issuance of stock rights, specified extraordinary distributions and similar events. Pursuant to authoritative accounting guidance, Digital Realty Trust, Inc. evaluated whether it controls the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the share settlement of the noncontrolling Operating Partnership common and incentive units. Based on the results of this analysis, we concluded that the common units and incentive units of the Operating Partnership met the criteria to be classified within equity, except for certain common units issued to certain former unitholders in DuPont Fabros Technology, L.P. ("DFT Operating Partnership") in the DuPont Fabros Technology merger ("DFT Merger"), which are subject to certain restrictions and, accordingly, are not presented as permanent equity in the condensed consolidated balance sheet. In connection with the initial public offering of DuPont Fabros Technology, Inc. ("DFT") in 2007, DFT, the DFT Operating Partnership and certain DFT Operating Partnership unitholders entered into a tax protection agreement to assist such unitholders in deferring certain U.S. federal income tax liabilities that may have otherwise resulted from the contribution transactions undertaken in connection with the initial public offering and the ownership of interests in the DFT Operating Partnership and to set forth certain agreements with respect to other tax matters. In connection with the DFT Merger, certain DFT Operating Partnership unitholders entered into a new tax protection agreement with Digital Realty Trust, Inc. and the Operating Partnership that replaced and superseded the DFT tax protection agreement, effective as of the closing of the DFT Merger. Pursuant to the new tax protection agreement, such DFT Operating Partnership unitholders entered into a guarantee of certain debt of a subsidiary of the Operating Partnership. The Operating Partnership must offer such DFT Operating Partnership unitholders a new guarantee opportunity in the event any guaranteed debt is repaid prior to March 1, 2023. If the Operating Partnership fails to offer the guarantee opportunity or to allocate guaranteed debt to any such DFT Operating Partnership unitholder as required under the new tax protection agreement, the Operating Partnership generally would be required to indemnify each such DFT Operating Partnership unitholder for the tax liability resulting from such failure, as determined under the new tax protection agreement. The redemption value of the noncontrolling Operating Partnership common units and the vested incentive units was approximately $891.0 million and $887.0 million based on the closing market price of Digital Realty Trust, Inc. common stock on September 30, 2018 and December 31, 2017 , respectively. The following table shows activity for the noncontrolling interests in the Operating Partnership for the nine months ended September 30, 2018 : Common Units Incentive Units Total As of December 31, 2017 6,899,094 1,590,001 8,489,095 Redemption of common units for shares of Digital Realty Trust, Inc. common stock (1) (487,610 ) — (487,610 ) Conversion of incentive units held by employees and directors for shares of Digital Realty Trust, Inc. common stock (1) — (80,182 ) (80,182 ) Incentive units issued upon achievement of market performance condition — 326,947 326,947 Grant of incentive units to employees and directors — 114,472 114,472 Cancellation / forfeitures of incentive units held by employees and directors — (22,135 ) (22,135 ) As of September 30, 2018 6,411,484 1,929,103 8,340,587 (1) Redemption of common units were recorded as a reduction to noncontrolling interests in the Operating Partnership and an increase to common stock and additional paid in capital based on the book value per unit in the accompanying condensed consolidated balance sheet of Digital Realty Trust, Inc. (c) Dividends We have declared and paid the following dividends on our common and preferred stock for the nine months ended September 30, 2018 (in thousands, except per share data): Date dividend declared Dividend Series C Preferred Stock Series G Preferred Stock Series H Preferred Stock Series I Preferred Stock Series J Preferred Stock Common March 1, 2018 March 30, 2018 $ 3,333 $ 3,672 $ 6,730 $ 3,969 $ 2,625 $ 208,015 May 8, 2018 June 29, 2018 3,333 3,672 6,730 3,969 2,625 208,071 August 14, 2018 September 28, 2018 3,333 3,672 6,730 3,969 2,625 208,166 $ 9,999 $ 11,016 $ 20,190 $ 11,907 $ 7,875 $ 624,252 Annual rate of dividend per share $ 1.65625 $ 1.46875 $ 1.84375 $ 1.58750 $ 1.31250 $ 4.04000 Distributions out of Digital Realty Trust, Inc.’s current or accumulated earnings and profits are generally classified as dividends whereas distributions in excess of its current and accumulated earnings and profits, to the extent of a stockholder’s U.S. federal income tax basis in Digital Realty Trust, Inc.’s stock, are generally classified as a return of capital. Distributions in excess of a stockholder’s U.S. federal income tax basis in Digital Realty Trust, Inc.’s stock are generally characterized as capital gain. Cash provided by operating activities has generally been sufficient to fund all distributions, however, in the future we may also need to utilize borrowings under the global revolving credit facility to fund all or a portion of distributions. (d) Accumulated Other Comprehensive Loss, Net The accumulated balances for each item within other comprehensive income (loss), net are as follows (in thousands): Foreign currency Cash flow hedge Foreign currency net investment hedge adjustments Accumulated other Balance as of December 31, 2017 $ (147,370 ) $ 13,200 $ 25,738 $ (108,432 ) Net current period change (8,272 ) 15,705 — 7,433 Reclassification to interest expense from interest — (2,202 ) — (2,202 ) Balance as of September 30, 2018 $ (155,642 ) $ 26,703 $ 25,738 $ (103,201 )

Capital and Accumulated Other C

Capital and Accumulated Other Comprehensive Loss	9 Months Ended
	Sep. 30, 2018
Digital Realty Trust, L.P.
Class of Stock [Line Items]
Capital and Accumulated Other Comprehensive Loss	Capital and Accumulated Other Comprehensive Loss (a) Allocations of Net Income and Net Losses to Partners Except for special allocations to holders of profits interest units described below in Note 13(a) under the heading “Incentive Plan—Long-Term Incentive Units,” the Operating Partnership’s net income will generally be allocated to Digital Realty Trust, Inc. (the General Partner) to the extent of the accrued preferred return on its preferred units, and then to the General Partner and the Operating Partnership’s limited partners in accordance with the respective percentage interests in the common units issued by the Operating Partnership. Net loss will generally be allocated to the General Partner and the Operating Partnership’s limited partners in accordance with the respective common percentage interests in the Operating Partnership until the limited partner’s capital is reduced to zero and any remaining net loss would be allocated to the General Partner. However, in some cases, losses may be disproportionately allocated to partners who have guaranteed our debt. The allocations described above are subject to special allocations relating to depreciation deductions and to compliance with the provisions of Sections 704(b) and 704(c) of the Code, and the associated Treasury Regulations. (b) Forward Equity Sale On September 27, 2018, Digital Realty Trust, Inc. completed an underwritten public offering of 9,775,000 shares of its common stock (including 1,275,000 shares from the exercise in full of the underwriters' option to purchase additional shares), all of which were offered in connection with forward sale agreements it entered into with certain financial institutions acting as forward purchasers. The forward purchasers borrowed and sold an aggregate of 9,775,000 shares of Digital Realty Trust, Inc.’s common stock in the public offering. Digital Realty Trust, Inc. did not receive any proceeds from the sale of our common stock by the forward purchasers in the public offering. The Company expects to receive net proceeds of approximately $1.1 billion (net of fees and estimated expenses) upon full physical settlement of the forward sale agreements, which is anticipated to be no later than September 27, 2019. Upon physical settlement of the forward sale agreements, the Operating Partnership is expected to issue partnership units to Digital Realty Trust, Inc. in exchange for contribution of the net proceeds. (c) Partnership Units Limited partners have the right to require the Operating Partnership to redeem part or all of their common units for cash based on the fair market value of an equivalent number of shares of the General Partner’s common stock at the time of redemption. Alternatively, the General Partner may elect to acquire those common units in exchange for shares of the General Partner’s common stock on a one -for-one basis, subject to adjustment in the event of stock splits, stock dividends, issuance of stock rights, specified extraordinary distributions and similar events. Pursuant to authoritative accounting guidance, Digital Realty Trust, Inc. evaluated whether it controls the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the share settlement of the noncontrolling Operating Partnership common and incentive units. Based on the results of this analysis, we concluded that the common units and incentive units of the Operating Partnership met the criteria to be classified within capital, except for certain common units issued to certain former DFT Operating Partnership unitholders in the DFT Merger, which are subject to certain restrictions and, accordingly, are not presented as permanent capital in the condensed consolidated balance sheet. In connection with the initial public offering of DFT in 2007, DFT, the DFT Operating Partnership and certain DFT Operating Partnership unitholders entered into a tax protection agreement to assist such unitholders in deferring certain U.S. federal income tax liabilities that may have otherwise resulted from the contribution transactions undertaken in connection with the initial public offering and the ownership of interests in the DFT Operating Partnership and to set forth certain agreements with respect to other tax matters. In connection with the DFT Merger, certain DFT Operating Partnership unitholders entered into a new tax protection agreement with Digital Realty Trust, Inc. and the Operating Partnership that replaced and superseded the DFT tax protection agreement, effective as of the closing of the DFT Merger. Pursuant to the new tax protection agreement, such DFT Operating Partnership unitholders entered into a guarantee of certain debt of a subsidiary of the Operating Partnership. The Operating Partnership must offer such DFT Operating Partnership unitholders a new guarantee opportunity in the event any guaranteed debt is repaid prior to March 1, 2023. If the Operating Partnership fails to offer the guarantee opportunity or to allocate guaranteed debt to any such DFT Operating Partnership unitholder as required under the new tax protection agreement, the Operating Partnership generally would be required to indemnify each such DFT Operating Partnership unitholder for the tax liability resulting from such failure, as determined under the new tax protection agreement. The redemption value of the limited partners’ common units and the vested incentive units was approximately $891.0 million and $887.0 million based on the closing market price of Digital Realty Trust, Inc.’s common stock on September 30, 2018 and December 31, 2017 , respectively. (d) Distributions All distributions on the Operating Partnership’s units are at the discretion of Digital Realty Trust, Inc.’s board of directors. The Operating Partnership has declared and paid the following distributions on its common and preferred units for the nine months ended September 30, 2018 (in thousands, except for per unit data): Date distribution declared Distribution Series C Preferred Units Series G Preferred Units Series H Preferred Units Series I Preferred Units Series J Preferred Units Common March 1, 2018 March 30, 2018 $ 3,333 $ 3,672 $ 6,730 $ 3,969 $ 2,625 $ 216,953 May 8, 2018 June 29, 2018 3,333 3,672 6,730 3,969 2,625 216,789 August 14, 2018 September 28, 2018 3,333 3,672 6,730 3,969 2,625 216,825 $ 9,999 $ 11,016 $ 20,190 $ 11,907 $ 7,875 $ 650,567 Annual rate of distribution per unit $ 1.65625 $ 1.46875 $ 1.84375 $ 1.58750 $ 1.31250 $ 4.04000 (e) Accumulated Other Comprehensive Loss The accumulated balances for each item within other comprehensive income are as follows (in thousands): Foreign currency Cash flow hedge Foreign currency net investment hedge adjustments Accumulated other Balance as of December 31, 2017 $ (151,795 ) $ 12,758 $ 26,152 $ (112,885 ) Net current period change (8,608 ) 16,336 — 7,728 Reclassification to interest expense from interest rate swaps — (2,289 ) — (2,289 ) Balance as of September 30, 2018 $ (160,403 ) $ 26,805 $ 26,152 $ (107,446 )

Incentive Plan

Incentive Plan	9 Months Ended
	Sep. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Incentive Plan	Incentive Plan On April 28, 2014, our stockholders approved the Digital Realty Trust, Inc., Digital Services, Inc., and Digital Realty Trust, L.P. 2014 Incentive Award Plan (as amended, the 2014 Incentive Award Plan). The 2014 Incentive Award Plan became effective and replaced the Amended and Restated 2004 Incentive Award Plan, as amended, as of the date of such stockholder approval. The material features of the 2014 Incentive Award Plan are described in our definitive Proxy Statement filed on March 19, 2014 in connection with the 2014 Annual Meeting, which description is incorporated herein by reference. Effective as of September 14, 2017, the 2014 Incentive Award Plan was amended to provide that shares which remained available for issuance under DFT’s Amended and Restated 2011 Equity Incentive Plan immediately prior to the closing of the DFT Merger (as adjusted and converted into shares of Digital Realty Trust, Inc.’s common stock) may be used for awards under the 2014 Incentive Award Plan and will not reduce the shares authorized for grant under the 2014 Incentive Award Plan, to the extent that using such shares is permitted without stockholder approval under applicable stock exchange rules. In connection with the amendment to the 2014 Incentive Award Plan, on September 22, 2017, Digital Realty Trust, Inc. registered an additional 3.7 million shares that may be issued pursuant to the 2014 Incentive Award Plan. As of September 30, 2018 , approximately 7.1 million shares of common stock, including awards convertible into or exchangeable for shares of common stock, remained available for future issuance under the 2014 Incentive Award Plan. Each long-term incentive unit and each Class D unit issued under the 2014 Incentive Award Plan counts as one share of common stock for purposes of calculating the limit on shares that may be issued under the 2014 Incentive Award Plan and the individual award limits set forth therein. Below is a summary of our compensation expense for the three and nine months ended September 30, 2018 and 2017 and our unearned compensation as of September 30, 2018 and December 31, 2017 (in millions): Deferred Compensation Unearned Compensation Expected period to recognize unearned compensation (in years) Expensed Capitalized As of September 30, 2018 As of December 31, 2017 Three Months Ended September 30, Type of incentive award 2018 2017 2018 2017 Long-term incentive units $ 1.2 $ 0.8 $ 0.1 $ 0.6 $ 11.0 $ 6.9 3.0 Market performance-based awards 3.1 2.7 0.3 0.6 28.4 24.7 2.1 Restricted stock 1.5 1.1 1.1 0.8 23.4 17.5 2.8 Nine Months Ended September 30, 2018 2017 2018 2017 Long-term incentive units $ 5.2 $ 3.4 $ 0.2 $ 1.4 Market performance-based awards 10.0 7.3 0.7 1.9 Restricted stock 4.7 3.3 3.2 2.5 (a) Long-Term Incentive Units Long-term incentive units, which are also referred to as profits interest units, may be issued to eligible participants for the performance of services to or for the benefit of the Operating Partnership. Long-term incentive units (other than Class D units), whether vested or not, will receive the same quarterly per unit distributions as Operating Partnership common units, which equal the per share distributions on Digital Realty Trust, Inc. common stock. Initially, long-term incentive units do not have full parity with common units with respect to liquidating distributions. If such parity is reached, vested long-term incentive units may be converted into an equal number of common units of the Operating Partnership at any time, and thereafter enjoy all the rights and privileges of common units of the Operating Partnership, including redemption rights. For a discussion of how long-term incentive units achieve parity with common units, see Note 14(a) to our consolidated financial statements for the fiscal year ended December 31, 2017 , included in our Annual Report on 10-K for the year ended December 31, 2017 . Below is a summary of our long-term incentive unit activity for the nine months ended September 30, 2018 . Unvested Long-term Incentive Units Units Weighted-Average Grant Date Fair Value Unvested, beginning of period 99,295 $ 90.59 Granted 114,472 101.26 Vested (49,054 ) 88.97 Cancelled or expired (14,275 ) 82.85 Unvested, end of period 150,438 $ 99.49 The grant date fair values, which equal the market price of Digital Realty Trust, Inc. common stock on the applicable grant date(s), are being expensed on a straight-line basis for service awards between two and four years, the current vesting period of the long-term incentive units. (b) Market Performance-Based Awards During the nine months ended September 30, 2018 and 2017 , the Compensation Committee of the Board of Directors of Digital Realty Trust, Inc. approved the grant of market performance-based Class D units of the Operating Partnership and market performance-based restricted stock units, or RSUs, covering shares of Digital Realty Trust, Inc.’s common stock (collectively, the “awards”), under the 2014 Incentive Award Plan to officers and employees of the Company. The awards, which were determined to contain a market condition, utilize total shareholder return, or TSR, over a three -year measurement period as the market performance metric. Awards will vest based on Digital Realty Trust, Inc.’s TSR relative to the MSCI US REIT Index, or RMS, over a three -year market performance period, or the Market Performance Period, commencing in January 2018 or January 2017, as applicable (or, if earlier, ending on the date on which a change in control of the Company occurs), subject to continued services. Vesting with respect to the market condition is measured based on the difference between Digital Realty Trust, Inc.’s TSR percentage and the TSR percentage of the RMS, or the RMS Relative Market Performance. In the event that the RMS Relative Market Performance during the Market Performance Period is achieved at the “threshold,” “target” or “high” level as set forth below, the awards will become vested as to the market condition with respect to the percentage of Class D units or RSUs, as applicable, set forth below: Level RMS Relative Market Performance Vesting Percentage Below Threshold Level ≤ -300 basis points 0% Threshold Level -300 basis points 25% Target Level 100 basis points 50% High Level > 500 basis points 100% If the RMS Relative Market Performance falls between the levels specified above, the percentage of the award that will vest with respect to the market condition will be determined using straight-line linear interpolation between such levels. In January 2018, following the completion of the applicable Market Performance Period, the Compensation Committee determined that the high level had been achieved for the 2015 awards and, accordingly, 363,193 class D units (including 36,246 distribution equivalent units that immediately vested on December 31, 2017 upon the high level being achieved) and 49,707 RSUs performance vested, subject to service-based vesting. On February 27, 2018, 50% of the 2015 awards vested and the remaining 50% will vest on February 27, 2019, subject to continued employment through each applicable vesting date. Following the completion of the applicable Market Performance Period, the 2017 awards that satisfy the market condition, if any, will vest 50% on February 27, 2020 and 50% on February 27, 2021, subject to continued employment through each applicable vesting date. Following the completion of the applicable Market Performance Period, the 2018 awards that satisfy the market condition, if any, will vest 50% on February 27, 2021 and 50% on February 27, 2022, subject to continued employment through each applicable vesting date. In the event of a change in control, termination of employment by the Company without cause, or termination of employment by the award recipient for good reason, death, disability or retirement, service-based vesting will be accelerated, in full or on a pro rata basis in any case prior to the completion of the Market Performance Period. However, vesting with respect to the market condition will continue to be measured based on RMS Relative Market Performance during the three -year Market Performance Period (or, in the case of a change in control, shortened Market Performance Period). The fair values of the 2018 awards and 2017 awards granted were measured using a Monte Carlo simulation to estimate the probability of the market vesting condition being satisfied. Digital Realty Trust, Inc.’s achievement of the market vesting condition is contingent on its TSR over a three -year market performance period, relative to the total shareholder return of the RMS. The Monte Carlo simulation is a probabilistic technique based on the underlying theory of the Black-Scholes formula, which was run for 100,000 trials to determine the fair value of the awards. For each trial, the payoff to an award is calculated at the settlement date and is then discounted to the grant date at a risk-free interest rate. The total expected value of the awards on the grant date was determined by multiplying the average value per award over all trials by the number of awards granted. Assumptions used in the valuations are summarized as follows: Award Date Expected Stock Price Volatility Risk-Free Interest rate January 1, 2017 25% 1.49% February 28, 2017 23% 1.43% January 1, 2018 22% 1.98% March 1, 2018 22% 2.34% March 9, 2018 22% 2.42% These valuations were performed in a risk-neutral framework, so no assumption was made with respect to an equity risk premium. As of September 30, 2018 , 2,165,692 Class D units and 590,569 market performance-based RSUs had been awarded to our executive officers and other employees. The number of units granted reflects the maximum number of Class D units or market performance-based RSUs, as applicable, which will become vested assuming the achievement of the highest level of RMS Relative Market Performance under the awards and, in the case of the Class D units, also includes distribution equivalent units. The fair value of these awards of approximately $96.7 million will be recognized as compensation expense on a straight-line basis over the expected service period of approximately four years. If the market conditions are not met, at the end of the applicable performance periods, the unamortized amount will be recognized as an expense at that time. (c) Restricted Stock Below is a summary of our restricted stock activity for the nine months ended September 30, 2018 . Unvested Restricted Stock Shares Weighted-Average Grant Date Fair Value Unvested, beginning of period 259,422 $ 90.54 Granted 164,748 101.24 Vested (92,432 ) 82.96 Cancelled or expired (28,510 ) 96.69 Unvested, end of period 303,228 $ 97.21 The grant date fair values, which equal the market price of Digital Realty Trust, Inc. common stock on the grant date, are expensed on a straight-line basis for service awards over the vesting period of the restricted stock, which is generally four years.

Derivative Instruments

Derivative Instruments	9 Months Ended
	Sep. 30, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	Derivative Instruments Currently, we use interest rate swaps to manage our interest rate risk. The valuation of these instruments is determined using widely accepted valuation techniques including discounted cash flow analysis on the expected cash flows of each derivative. This analysis reflects the contractual terms of the derivatives, including the period to maturity, and uses observable market-based inputs, including interest rate curves. The fair values of interest rate swaps are determined using the market standard methodology of netting the discounted future fixed cash receipts (or payments) and the discounted expected variable cash payments (or receipts). The variable cash payments (or receipts) are based on an expectation of future interest rates (forward curves) derived from observable market interest rate curves. To comply with the provisions of fair value accounting guidance, we incorporate credit valuation adjustments to appropriately reflect both our own nonperformance risk and the respective counterparty’s nonperformance risk in the fair value measurements. In adjusting the fair value of our derivative contracts for the effect of nonperformance risk, we have considered the impact of netting and any applicable credit enhancements, such as collateral postings, thresholds, mutual puts, and guarantees. Although we have determined that the majority of the inputs used to value our derivatives fall within Level 2 of the fair value hierarchy, the credit valuation adjustments associated with our derivatives utilize Level 3 inputs, such as estimates of current credit spreads to evaluate the likelihood of default by us and our counterparties. However, as of September 30, 2018 , we have assessed the significance of the impact of the credit valuation adjustments on the overall valuation of our derivative positions and have determined that the credit valuation adjustments are not significant to the overall valuation of our derivatives. As a result, we have determined that our derivative valuations in their entirety are classified in Level 2 of the fair value hierarchy. We do not have any fair value measurements on a recurring basis using significant unobservable inputs (Level 3) as of September 30, 2018 or December 31, 2017 . The Company presents its interest rate derivatives in its condensed consolidated balance sheets on a gross basis as interest rate swap assets (recorded in other assets) and interest rate swap liabilities (recorded in accounts payable and other accrued liabilities). As of September 30, 2018 , there was no impact from netting arrangements as the Company did not have any derivatives in liability positions. Cash Flow Hedges of Interest Rate Risk Our objectives in using interest rate derivatives are to add stability to interest expense and to manage our exposure to interest rate movements related to certain floating rate debt obligations. To accomplish this objective, we primarily use interest rate swaps as part of our interest rate risk management strategy. Interest rate swaps designated as cash flow hedges involve the receipt of variable-rate amounts from a counterparty in exchange for making fixed-rate payments over the life of the agreements without exchange of the underlying notional amount. We record all our interest rate swaps on the condensed consolidated balance sheet at fair value. In determining the fair value of our interest rate swaps, we consider the credit risk of our counterparties. These counterparties are generally larger financial institutions engaged in providing a variety of financial services. These institutions generally face similar risks regarding adverse changes in market and economic conditions, including, but not limited to, fluctuations in interest rates, exchange rates, equity and commodity prices and credit spreads. The recent and pervasive disruptions in the financial markets have heightened the risks to these institutions. As of September 30, 2018 and December 31, 2017 , we had the following outstanding interest rate derivatives that were designated as effective cash flow hedges of interest rate risk (in thousands): Notional Amount Fair Value at Significant Other As of September 30, 2018 As of December 31, 2017 Type of Strike Effective Date Expiration Date As of September 30, 2018 (5) As of December 31, 2017 (5) Currently-paying contracts $ 206,000 (1) $ 206,000 (1) Swap 1.611 Jun 15, 2017 Jan 15, 2020 $ 2,856 $ 1,409 54,905 (1) 54,905 (1) Swap 1.605 Jun 6, 2017 Jan 6, 2020 747 374 75,000 (1) 75,000 (1) Swap 1.016 Apr 6, 2016 Jan 6, 2021 3,023 2,260 75,000 (1) 75,000 (1) Swap 1.164 Jan 15, 2016 Jan 15, 2021 2,808 1,947 300,000 (2) 300,000 (2) Swap 1.435 Jan 15, 2016 Jan 15, 2023 17,829 9,978 220,843 (3) 229,012 (3) Swap 0.792 Jan 15, 2016 Jan 15, 2019 (24 ) (430 ) 76,298 (4) 78,357 (4) Swap 0.779 Jan 15, 2016 Jan 15, 2021 2,960 3,034 $ 1,008,046 $ 1,018,274 $ 30,199 $ 18,572 (1) Represents portions of the U.S. dollar tranche of the 5 -Year Term Loan. (2) Represents the U.S. dollar tranche of the 7 -Year Term Loan. (3) Represents the British pound sterling tranche of the 5 -Year Term Loan. Translation to U.S. dollars is based on exchange rates of $1.30 to £1.00 as of September 30, 2018 and $1.35 to £1.00 as of December 31, 2017 . (4) Represents the Canadian dollar tranche of the 5 -Year Term Loan. Translation to U.S. dollars is based on exchange rates of $0.77 to 1.00 CAD as of September 30, 2018 and $0.80 to 1.00 CAD as of December 31, 2017 . (5) Balance recorded in other assets in the consolidated balance sheets if positive and recorded in accounts payable and other accrued liabilities in the consolidated balance sheets if negative. As of September 30, 2018 , we estimate that an additional $8.5 million will be reclassified as a decrease to interest expense during the twelve months ended September 30, 2019 , when the hedged forecasted transactions impact earnings. Foreign Currency Net Investment Hedges During the three months ended June 30, 2016, we entered into a series of forward contracts pursuant to which we agreed to sell an amount of foreign currency for an agreed upon amount of U.S. dollars. These forward contracts were executed to manage foreign currency exposures associated with certain transactions. As of June 30, 2016, the forward contracts did not meet the criteria for hedge accounting under GAAP and had a fair value of approximately $37.8 million . On July 1, 2016, the four forward contracts still in place met the criteria for net investment hedge accounting. During the year ended December 31, 2017 , we terminated the four forward contracts with a notional amount of GBP 357.3 million . In connection with the settlement, we received approximately $64.0 million in proceeds and the related amount of approximately $26.2 million of accumulated other comprehensive income (AOCI) will remain in AOCI until the Company sells or liquidates its GBP-denominated investments, which has not occurred as of September 30, 2018 . Credit-risk-related Contingent Features We have agreements with each of our derivative counterparties that contain a provision where we could be declared in default on our derivative obligations if repayment of the underlying indebtedness is accelerated by the lender due to our default on the indebtedness. As of September 30, 2018 , we did not have any derivatives in a net liability position, and have not posted any collateral related to these agreements.

Fair Value of Financial Instrum

Fair Value of Financial Instruments	9 Months Ended
	Sep. 30, 2018
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	Fair Value of Financial Instruments We disclose fair value information about all financial instruments, whether or not recognized in the condensed consolidated balance sheets, for which it is practicable to estimate fair value. Current accounting guidance requires the Company to disclose fair value information about all financial instruments, whether or not recognized in the balance sheets, for which it is practicable to estimate fair value. The Company’s disclosures of estimated fair value of financial instruments at September 30, 2018 and December 31, 2017 were determined using available market information and appropriate valuation methods. Considerable judgment is necessary to interpret market data and develop estimated fair value. The use of different market assumptions or estimation methods may have a material effect on the estimated fair value amounts. The carrying amounts for cash and cash equivalents, restricted cash, accounts and other receivables, accounts payable and other accrued liabilities, accrued dividends and distributions, security deposits and prepaid rents approximate fair value because of the short-term nature of these instruments. As described in Note 14 "Derivative Instruments", the interest rate swaps are recorded at fair value. We calculate the fair value of our mortgage loans, unsecured term loan and unsecured senior notes based on currently available market rates assuming the loans are outstanding through maturity and considering the collateral and other loan terms. In determining the current market rate for fixed rate debt, a market spread is added to the quoted yields on federal government treasury securities with similar maturity dates to our debt. The carrying value of our global revolving credit facility approximates fair value, due to the variability of interest rates. As of September 30, 2018 and December 31, 2017 , the aggregate estimated fair value and carrying value of our global revolving credit facility, unsecured term loans, unsecured senior notes and mortgage loans were as follows (in thousands): Categorization under the fair value hierarchy As of September 30, 2018 As of December 31, 2017 Estimated Fair Value Carrying Value Estimated Fair Value Carrying Value Global revolving credit facility (1)(5) Level 2 $ 594,983 $ 594,983 $ 558,191 $ 558,191 Unsecured term loans (2)(6) Level 2 1,356,702 1,356,702 1,425,117 1,425,117 Unsecured senior notes (3)(4)(7) Level 2 7,280,877 7,168,825 6,976,603 6,608,545 Mortgage loans (3)(8) Level 2 106,424 106,101 106,523 106,611 $ 9,338,986 $ 9,226,611 $ 9,066,434 $ 8,698,464 (1) The carrying value of our global revolving credit facility approximates estimated fair value, due to the variability of interest rates and the stability of our credit ratings. (2) The carrying value of our unsecured term loans approximates estimated fair value, due to the variability of interest rates and the stability of our credit ratings. (3) Valuations for our unsecured senior notes and mortgage loans are determined based on the expected future payments discounted at risk-adjusted rates. The 2019 Notes, 5.875% 2020 Notes, 3.400% 2020 Notes, 2021 Notes, 3.950% 2022 Notes, 3.625% 2022 Notes, 4.750% 2023 Notes, 2.750% 2023 Notes, 2.625% 2024 Notes, 2.750% 2024 Notes, 4.750% 2025 Notes, 4.250% 2025 Notes, 2027 Notes, 2028 Notes and 2029 Notes are valued based on quoted market prices. (4) The carrying value of the 5.875% 2020 Notes, 3.400% 2020 Notes, 2021 Notes, 3.625% 2022 Notes, 3.950% 2022 Notes, 4.750% 2023 Notes, 2.750% 2023 Notes, 2.625% 2024 Notes, 2.750% 2024 Notes, 4.250% 2025 Notes, 2027 Notes, 2028 Notes and 2029 Notes are net of discount of $16.5 million and $18.5 million in the aggregate as of September 30, 2018 and December 31, 2017 , respectively. (5) The estimated fair value and carrying value are exclusive of deferred financing costs of $4.7 million and $7.2 million as of September 30, 2018 and December 31, 2017 , respectively. (6) The estimated fair value and carrying value are exclusive of deferred financing costs of $3.7 million and $4.8 million as of September 30, 2018 and December 31, 2017 , respectively. (7) The estimated fair value and carrying value are exclusive of deferred financing costs of $38.3 million and $37.8 million as of September 30, 2018 and December 31, 2017 , respectively. (8) The estimated fair value and carrying value are exclusive of deferred financing costs of $0.0 million and $0.0 million as of September 30, 2018 and December 31, 2017 , respectively.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies (a) Construction Commitments Our properties require periodic investments of capital for tenant-related capital expenditures and for general capital improvements including ground up construction. From time to time in the normal course of our business, we enter into various construction contracts with third parties that may obligate us to make payments. At September 30, 2018 , we had open commitments, including amounts reimbursable of approximately $5.7 million , related to construction contracts of approximately $428.3 million . (b) Legal Proceedings The Company is involved in legal proceedings arising in the ordinary course of business from time to time. As of September 30, 2018 , the Company is not currently a party to any legal proceedings that it believes would have a material adverse effect on its financial position, results of operations or liquidity nor, to its knowledge, are any such legal proceedings threatened against it.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2018
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events On October 24, 2018, we refinanced our global revolving credit facility and entered into a global senior credit agreement for a $2.35 billion senior unsecured revolving credit facility, which we refer to as the 2018 global revolving credit facility, that replaced the $2.0 billion revolving credit facility executed on January 15, 2016. The 2018 global revolving credit facility provides for borrowings in Australian dollars, British pounds sterling, Canadian dollars, Euros, Hong Kong dollars, Japanese yen, Singapore dollars, and U.S. dollars, and includes the ability to add additional currencies in the future. The 2018 global revolving credit facility matures on January 24, 2023 with two six -month extension options. In addition, we have the ability from time to time to increase the size of the global revolving credit facility and the unsecured term loans (discussed below), in any combination, by up to $1.25 billion , subject to receipt of lender commitments and other conditions precedent. On October 24, 2018, we refinanced our senior unsecured multi-currency term loan facility and entered into an amended and restated term loan agreement, which we refer to as the 2018 term loan agreement, which governs (i) a $300.0 million 5 -year senior unsecured term loan, which we refer to as the 2023 Term Loan and (ii) an approximately $512.0 million 5 -year senior unsecured term loan, which we refer to as the 2024 Term Loan. The 2018 term loan agreement replaced the $1.55 billion term loan agreement executed on January 15, 2016. The 2018 term loan agreement provides for borrowings in Australian dollars, Canadian dollars, Hong Kong dollars, Singapore dollars and U.S. dollars. In addition, we have the ability from time to time to increase the aggregate size of lending under the 2018 term loan agreement and the global revolving credit facility (discussed above), in any combination, by up to $1.25 billion , subject to receipt of lender commitments and other conditions precedent. The maturity date of the 2023 Term Loan is January 15, 2023. The maturity date of the 2024 Term Loan is January 24, 2023 with two six -month extension options. On October 24, 2018, we entered into a credit agreement for a ¥33.3 billion (approximately $296.5 million based on the exchange rate on October 24, 2018) senior unsecured revolving credit facility, which we refer to as the Yen revolving credit facility. The Yen revolving credit facility provides for borrowings in Japanese yen. In addition, we have the ability from time to time to increase the size of the Yen revolving credit facility to up to ¥93.3 billion (approximately $831.1 million based on the exchange rate on October 24, 2018), subject to receipt of lender commitments and other conditions precedent. The Yen revolving credit facility matures on January 24, 2024. On October 24, 2018, the Operating Partnership, together with its subsidiary Quill Equity LLC as borrowers, entered into Amendment No. 1 to the Senior Secured Term Loan, which we refer to (as so amended) as the secured term loan agreement, which among other things amended the financial covenants therein to correspond with the financial covenants in the 2018 global senior credit agreement and the 2018 term loan agreement, decreased the applicable rate for eurodollar rate advances, and decreased the applicable rate for base rate advances. As of October 24, 2018, the applicable rate for eurodollar rate advances is the applicable index plus 100 basis points and the applicable rate for base rate advances is the applicable index plus 0 basis points. An annual agency fee is payable quarterly in respect of the commitments under the secured term loan agreement. We are also required to pay certain fees to the administrative agent under the secured term loan agreement.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2018
Accounting Policies [Abstract]
Principles of Consolidation and Basis of Presentation	Principles of Consolidation and Basis of Presentation The accompanying interim condensed consolidated financial statements include all of the accounts of Digital Realty Trust, Inc., the Operating Partnership and the subsidiaries of the Operating Partnership. Intercompany balances and transactions have been eliminated. The accompanying interim condensed consolidated financial statements are unaudited, but have been prepared in accordance with U.S. generally accepted accounting principles (U.S. GAAP) for interim financial information and in compliance with the rules and regulations of the United States Securities and Exchange Commission. Accordingly, they do not include all of the disclosures required by U.S. GAAP for complete financial statements. In the opinion of management, all adjustments necessary for a fair presentation have been included. All such adjustments are considered to be of a normal recurring nature, except as otherwise indicated. The results of operations for the interim periods are not necessarily indicative of the results to be obtained for the full fiscal year. These condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and the notes thereto included in our annual report on Form 10-K for the year ended December 31, 2017 . The notes to the condensed consolidated financial statements of Digital Realty Trust, Inc. and the Operating Partnership have been combined to provide the following benefits: • enhancing investors’ understanding of the Company and the Operating Partnership by enabling investors to view the business as a whole in the same manner as management views and operates the business; • eliminating duplicative disclosure and providing a more streamlined and readable presentation since a substantial portion of the disclosure applies to both the Company and the Operating Partnership; and • creating time and cost efficiencies through the preparation of one set of notes instead of two separate sets of notes. There are a few differences between the Company and the Operating Partnership, which are reflected in these condensed consolidated financial statements. We believe it is important to understand the differences between the Company and the Operating Partnership in the context of how we operate as an interrelated consolidated company. Digital Realty Trust, Inc.’s only material asset is its ownership of partnership interests of the Operating Partnership. As a result, Digital Realty Trust, Inc. generally does not conduct business itself, other than acting as the sole general partner of the Operating Partnership, issuing public securities from time to time and guaranteeing certain unsecured debt of the Operating Partnership and certain of its subsidiaries and affiliates. Digital Realty Trust, Inc. itself has not issued any indebtedness but guarantees the unsecured debt of the Operating Partnership and certain of its subsidiaries and affiliates, as disclosed in these notes. The Operating Partnership holds substantially all the assets of the Company and holds the ownership interests in the Company’s joint ventures. The Operating Partnership conducts the operations of the business and is structured as a partnership with no publicly traded equity. Except for net proceeds from public equity issuances by Digital Realty Trust, Inc., which are generally contributed to the Operating Partnership in exchange for partnership units, the Operating Partnership generally generates the capital required by the Company’s business primarily through the Operating Partnership’s operations, by the Operating Partnership’s or its affiliates' direct or indirect incurrence of indebtedness or through the issuance of partnership units. The presentation of noncontrolling interests in operating partnership, stockholders’ equity and partners’ capital are the main areas of difference between the condensed consolidated financial statements of Digital Realty Trust, Inc. and those of the Operating Partnership. The common limited partnership interests held by the limited partners in the Operating Partnership are presented as limited partners’ capital within partners’ capital in the Operating Partnership’s condensed consolidated financial statements and as noncontrolling interests in operating partnership within equity in Digital Realty Trust, Inc.’s condensed consolidated financial statements. The common and preferred partnership interests held by Digital Realty Trust, Inc. in the Operating Partnership are presented as general partner’s capital within partners’ capital in the Operating Partnership’s condensed consolidated financial statements and as preferred stock, common stock, additional paid-in capital and accumulated dividends in excess of earnings within stockholders’ equity in Digital Realty Trust, Inc.’s condensed consolidated financial statements. The differences in the presentations between stockholders’ equity and partners’ capital result from the differences in the equity issued at the Digital Realty Trust, Inc. and the Operating Partnership levels. To help investors understand the significant differences between the Company and the Operating Partnership, these consolidated financial statements present the following separate sections for each of the Company and the Operating Partnership: • condensed consolidated face financial statements; and • the following notes to the condensed consolidated financial statements: • "Debt of the Company" and "Debt of the Operating Partnership"; • "Income per Share" and "Income per Unit"; and • "Equity and Accumulated Other Comprehensive Loss, Net of the Company" and "Capital and Accumulated Other Comprehensive Loss of the Operating Partnership". In the sections that combine disclosure of Digital Realty Trust, Inc. and the Operating Partnership, these notes refer to actions or holdings as being actions or holdings of the Company. Although the Operating Partnership is generally the entity that enters into contracts and joint ventures and holds assets and debt, reference to the Company is appropriate because the business is one enterprise and the Company generally operates the business through the Operating Partnership.
Cash Equivalents	Cash Equivalents For the purpose of the condensed consolidated statements of cash flows, we consider short-term investments with original maturities of 90 days or less to be cash equivalents. As of September 30, 2018 , cash equivalents consist of investments in money market instruments.
Investment in Unconsolidated Joint Ventures	Investments in Unconsolidated Joint Ventures The Company’s investments in unconsolidated joint ventures are accounted for using the equity method, whereby our investment is increased for capital contributed and our share of the joint venture's net income and decreased by distributions we receive and our share of any losses of the joint ventures. We do not record losses of the joint ventures in excess of our investment balances unless we are liable for the obligations of the joint venture or are otherwise committed to provide financial support to the joint venture. Likewise, and as long as we have no explicit or implicit obligations to the joint venture, we will suspend equity method accounting to the extent that cash distributions exceed our investment balances until those unrecorded earnings exceed the excess distributions previously recognized in income. In this case, we will apply cost accounting concepts which tie income recognition to the receipt of cash. Cost basis accounting concepts will apply until earnings exceed the excess distributions previously recognized in income. We amortize the difference between the cost of our investments in the joint ventures and the book value of the underlying equity into income on a straight-line basis consistent with the lives of the underlying assets. The amortization of this difference was immaterial for the three and nine months ended September 30, 2018 and 2017 , respectively.
Capitalization of Costs	Capitalization of Costs Direct and indirect project costs that are clearly associated with the development of properties are capitalized as incurred. Project costs include all costs directly associated with the development of a property, including construction costs, interest, property taxes, insurance, legal fees and costs of personnel working on the project. Indirect costs that do not clearly relate to the projects under development are not capitalized and are charged to expense as incurred. Capitalization of costs begins when the activities necessary to get the development project ready for its intended use begins, which include costs incurred before the beginning of construction. Capitalization of costs ceases when the development project is substantially complete and ready for its intended use. Determining when a development project commences and when it is substantially complete and ready for its intended use involves a degree of judgment. We generally consider a development project to be substantially complete and ready for its intended use upon receipt of a certificate of occupancy. If and when development of a property is suspended pursuant to a formal change in the planned use of the property, we will evaluate whether the accumulated costs exceed the estimated value of the project and write off the amount of any such excess accumulated costs. For a development project that is suspended for reasons other than a formal change in the planned use of such property, the accumulated project costs are evaluated for impairment consistent with our impairment policies for long-lived assets. Capitalized costs are allocated to the specific components of a project that are benefited.
Goodwill	Goodwill Goodwill represents the excess of the purchase price over the fair value of net tangible and intangible assets acquired and tangible and intangible liabilities assumed in a business combination. Goodwill is not amortized. We perform an annual impairment test for goodwill and between annual tests, we evaluate goodwill for impairment whenever events or changes in circumstances occur that would more likely than not reduce the fair value of a reporting unit below its carrying value. In our impairment tests of goodwill, we first assess qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying value. If based on this assessment, we determine that the fair value of the reporting unit is not less than its carrying value, then performing the additional two-step impairment test is unnecessary. If our qualitative assessment indicates that goodwill impairment is more likely than not, we perform a two-step impairment test. We test goodwill for impairment under the two-step impairment test by first comparing the book value of net assets including goodwill to the fair value of the reporting unit. If the fair value is determined to be less than the book value of the net assets, including goodwill, a second step is performed to compute the amount of impairment as the difference between the implied fair value of goodwill and its carrying value. We estimate the fair value of the reporting units using discounted cash flows. If the carrying value of goodwill exceeds its implied fair value, an impairment charge is recognized. We have not recognized any goodwill impairments since our inception. Since some of the goodwill is denominated in foreign currencies, changes to the goodwill balance occur over time due to changes in foreign exchange rates.
Share-Based Compensation	Share-Based Compensation The Company measures all share-based compensation awards at fair value on the date they are granted to employees and directors, and recognizes compensation cost, net of forfeitures, over the requisite service period for awards with only a service condition. The estimated fair value of the long-term incentive units and Class D units (discussed in Note 13) granted by us is being amortized on a straight-line basis over the expected service period. The fair value of share-based compensation awards that contain a market condition is measured using a Monte Carlo simulation method and not adjusted based on actual achievement of the market condition.
Assets and Liabilities Measured at Fair Value	Assets and Liabilities Measured at Fair Value Fair value under U.S. GAAP is a market-based measurement, not an entity-specific measurement. Therefore, our fair value measurements are determined based on the assumptions that market participants would use in pricing the asset or liability. As a basis for considering market participant assumptions in fair-value measurements, we use a fair-value hierarchy that distinguishes between market participant assumptions based on market data obtained from sources independent of the reporting entity (observable inputs that are classified within Levels 1 and 2 of the hierarchy) and the reporting entity’s own assumptions about market participant assumptions (unobservable inputs classified within Level 3 of the hierarchy). Level 1 inputs utilize quoted prices (unadjusted) in active markets for identical assets or liabilities that the Company has the ability to access. Level 2 inputs are inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly or indirectly. Level 2 inputs may include quoted prices for similar assets and liabilities in active markets, as well as inputs that are observable for the asset or liability (other than quoted prices), such as interest rates, foreign exchange rates, and yield curves that are observable at commonly quoted intervals. Level 3 inputs are unobservable inputs for the asset or
Derivative Instruments	Derivative Instruments Derivative financial instruments are employed to manage risks, including foreign currency and interest rate exposures and are not used for trading or speculative purposes. As part of the Company’s risk management program, a variety of financial instruments, such as interest rate swaps and foreign exchange contracts, may be used to mitigate interest rate exposure and foreign currency exposure. The Company recognizes all derivative instruments in the balance sheet at fair value. Changes in the fair value of derivatives are recognized periodically either in earnings or in stockholders’ equity as a component of accumulated other comprehensive income (loss), depending on whether the derivative financial instrument is undesignated or qualifies for hedge accounting, and if so, whether it represents a fair value, cash flow, or net investment hedge. Gains and losses on derivatives designated as cash flow hedges, to the extent they are included in the assessment of effectiveness, are recorded in other comprehensive income (loss) and subsequently reclassified to earnings to offset the impact of the hedged items when they occur. In the event it becomes probable the forecasted transaction to which a cash flow hedge relates will not occur, the derivative would be terminated and the amount in other comprehensive income (loss) would be recognized in earnings. Changes in the fair value of derivatives that are designated and qualify as a hedge of the net investment in foreign operations, to the extent they are included in the assessment of effectiveness, are reported in other comprehensive income (loss) and are deferred until disposal of the underlying assets. Gains and losses representing components excluded from the assessment of effectiveness for cash flow and fair value hedges are recognized in earnings on a straight-line basis in the same caption as the hedged item over the term of the hedge. Gains and losses representing components excluded from the assessment of effectiveness for net investment hedges are recognized in earnings on a straight-line basis over the term of the hedge. The net interest paid or received on interest rate swaps is recognized as interest expense. Gains and losses resulting from the early termination of interest rate swap agreements are deferred and amortized as adjustments to interest expense over the remaining period of the debt originally covered by the terminated swap.
Income Taxes	Income Taxes Digital Realty Trust, Inc. has elected to be treated as a real estate investment trust (a “REIT”) for federal income tax purposes. As a REIT, Digital Realty Trust, Inc. generally is not required to pay federal corporate income tax to the extent taxable income is currently distributed to its stockholders. If Digital Realty Trust, Inc. fails to qualify as a REIT in any taxable year, it will be subject to federal income tax (including any applicable alternative minimum tax for taxable years prior to 2018) on its taxable income. The Company is subject to foreign, state and local income taxes in the jurisdictions in which it conducts business. The Company’s taxable REIT subsidiaries are subject to federal, state and foreign income taxes to the extent there is taxable income. Accordingly, the Company recognizes current and deferred income taxes for its taxable REIT subsidiaries, including federal, state and non-U.S. jurisdictions, as appropriate. We assess our significant tax positions in accordance with U.S. GAAP for all open tax years and determine whether we have any material unrecognized liabilities from uncertain tax benefits. If a tax position is not considered “more-likely-than-not” to be sustained solely on its technical merits, no benefits of the tax position are to be recognized (for financial statement purposes).
Presentation of Transactional-Based Taxes	Presentation of Transactional-based Taxes We account for transactional-based taxes, such as value added tax, or VAT, for our international properties on a net basis.
Redeemable Noncontrolling Interest	Redeemable Noncontrolling Interests Redeemable noncontrolling interests include amounts related to partnership units issued by consolidated subsidiaries of the Company in which redemption for equity is outside the control of the Company. Partnership units which are determined to be contingently redeemable for cash under the Financial Accounting Standards Board’s "Distinguishing Liabilities from Equity" guidance are classified as redeemable noncontrolling interests and presented in the mezzanine section between total liabilities and stockholder’s equity on the Company’s condensed consolidated balance sheets. The amounts of consolidated net income attributable to the Company and to the noncontrolling interests are presented on the Company’s condensed consolidated income statements.
Revenue Recognition	Revenue Recognition The majority of our revenue is derived from lease arrangements, which we account for in accordance with “Leases (Topic 840)”. We account for the non-lease components within our lease arrangements, as well as other sources of revenue, in accordance with “Revenue from Contracts with Customers (Topic 606)”. Revenue recognized as a result of applying Topic 840 was 97% and Topic 606 was 3% of total operating revenue for the three and nine months ended September 30, 2018 . Our leases are classified as operating leases and minimum rents are recognized on a straight-line basis over the terms of the leases, which may span multiple years. The excess of rents recognized over amounts contractually due pursuant to the underlying leases is included in deferred rent in the accompanying condensed consolidated balance sheets and contractually due but unpaid rents are included in accounts and other receivables. Tenant reimbursements for real estate taxes, common area maintenance, and other recoverable costs under our leases are recognized in the period that the expenses are incurred. Lease termination fees are recognized over the remaining term of the lease, effective as of the date the lease modification is finalized, assuming collection is not considered doubtful. As discussed above, we recognize amortization of the value of acquired above or below-market tenant leases as a reduction of rental revenue in the case of above-market leases or an increase to rental revenue in the case of below-market leases. Interconnection services are included in rental and other services on the condensed consolidated income statements and are generally provided on a month-to-month, one-year or multi-year term. Interconnection services include port and cross-connect services. Port services are typically sold on a one-year or multi-year term and revenue is recognized on a recurring monthly basis (straight-line). The Company bills customers on a monthly basis and recognizes the revenue over the period the service is provided. Revenue for cross-connect installations is generally recognized in the period the cross-connect is installed. Interconnection services that are not specific to a particular space are accounted for under Topic 606 and have terms that are generally one year or less. Occasionally, customers engage the Company for certain services. The nature of these services historically involves property management and construction management. The proper revenue recognition of these services can be different, depending on whether the arrangements are service revenue or contractor type revenue. Service revenues are typically recognized on an equal monthly basis based on the minimum fee to be earned. The monthly amounts could be adjusted depending on if certain performance milestones are met. Fee income arises primarily from contractual management agreements with entities in which we have a noncontrolling interest. The management fees are recognized as earned under the respective agreements. Management and other fee income related to partially owned noncontrolled entities are recognized to the extent attributable to the unaffiliated interest. We make subjective estimates as to when our revenue is earned and the collectability of our accounts receivable related to minimum rent, deferred rent, expense reimbursements, lease termination fees and other income. We specifically analyze accounts receivable and historical bad debts, customer concentrations, customer creditworthiness and current economic trends when evaluating the adequacy of the allowance for bad debts. These estimates have a direct impact on our net revenue because a higher bad debt allowance would result in lower net revenue, and recognizing rental revenue as earned in one period versus another would result in higher or lower net revenue for a particular period.
Transaction and Integration Expense	Transaction and Integration Expense Transaction and integration expense includes business combination expenses, other business development expenses and other expenses to integrate newly acquired investments, which are expensed as incurred. Transaction expenses include closing costs, broker commissions and other professional fees, including legal and accounting fees related to business combinations or acquisitions that were not consummated. Integration costs include transition costs associated with organizational restructuring (such as severance and retention payments and recruiting expenses), third-party consulting expenses directly related to the integration of acquired companies (in areas such as cost savings and synergy realization, technology and systems work), and internal costs such as training, travel and labor, reflecting time spent by Company personnel on integration activities and projects. Recurring costs are recorded in general and administrative expense.
Gains on Sale of Properties	Gains on Sale of Properties As of January 1, 2018, we began accounting for the sale of real estate properties under Financial Accounting Standards Board, or FASB, Accounting Standards Update, or ASU, No. 2017-05, Other Income—Gains and Losses from the Derecognition of Nonfinancial Assets (Subtopic 610-20), which provides for revenue recognition based on transfer of ownership. All properties were non-financial real estate assets and thus not businesses which were sold to noncustomers with no performance obligations subsequent to transfer of ownership
Management's Estimates	Management’s Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates made. On an on-going basis, we evaluate our estimates, including those related to the valuation of our real estate properties, tenant relationship value, goodwill, contingent consideration, accounts receivable and deferred rent receivable, performance-based equity compensation plans and the completeness of accrued liabilities. We base our estimates on historical experience, current market conditions, and various other assumptions that are believed to be reasonable under the circumstances. Actual results may vary from those estimates and those estimates could vary under different assumptions or conditions.
Segment and Geographic Information	Segment and Geographic Information All of our properties generate similar revenues and expenses related to tenant rent and services and reimbursements and operating expenses. The sale and delivery of our products is consistent across all properties and although services are provided to a wide range of customers, the types of real estate services provided to them are standardized throughout the portfolio. As such, the properties in our portfolio have similar economic characteristics and the nature of the products and services provided to our customers and the method to distribute such services are consistent throughout the portfolio. In addition, the chief operating decision makers evaluate operating performance and make resource allocation decisions for the portfolio as a whole, rather than by property type or revenue stream. Consequently, our properties qualify for aggregation into one reporting segment.
New Accounting Pronouncements	New Accounting Pronouncements New Accounting Standards Adopted In August 2017, the FASB issued ASU No. 2017-12, "Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities". The new standard amends the hedge accounting recognition and presentation requirements in Accounting Standards Codification, or ASC, 815. As permitted by ASU No. 2017-12, the Company early adopted this standard in the first quarter of 2018 on a prospective basis. Refer to Note 2(h), Derivative Instruments, for our policy related to the adoption of this standard. In January 2016, the FASB issued ASU No. 2016-01, "Recognition and Measurement of Financial Assets and Financial Liabilities". The guidance requires entities to measure equity investments that do not result in consolidation and are not accounted for under the equity method at fair value and to record changes in instruments specific credit risk for financial liabilities measured under the fair value option in other comprehensive income. The principal effect of ASU No. 2016-01 on our condensed consolidated financial statements is that, prior to adoption of ASU No. 2016-01, changes in the fair values of investments in equity securities with readily determinable fair values or redemption values were recognized in other comprehensive income until realized, while under ASU No. 2016-01 all changes in the fair values of these equity securities are recognized in current earnings. The update is effective for fiscal years beginning after December 15, 2017, and for interim periods therein. We adopted this standard in the first quarter of 2018 and the adoption did not have a material impact on our condensed consolidated financial statements. In May 2014, the FASB issued ASU No. 2014-09, "Revenue from Contracts with Customers (Topic 606)", and since that date has issued several additional ASUs intended to clarify certain aspects of ASU No. 2014-09 and to provide for certain practical expedients entities may elect upon adoption. Collectively, these ASUs outline a single comprehensive model for entities to use in accounting for revenues arising from contracts with customers. We adopted Topic 606 in the first quarter of 2018 using the modified retrospective transition method and applied Topic 606 to those contracts that were not completed as of January 1, 2018. The results for reporting periods beginning after January 1, 2018 are presented under Topic 606, while prior period amounts are not adjusted and continue to be presented under Topic 605. Our financial statements did not recognize a material effect from the cumulative impact of adopting Topic 606 as the new accounting standard does not impact lessor accounting. Refer to Note 2(l), Revenue Recognition, for the updated policy related to the adoption of this standard. New Accounting Standards Issued but not yet Adopted In February 2016, the FASB issued ASU No. 2016-02, "Leases (Topic 842)", which sets out the principles for the recognition, measurement, presentation and disclosure of leases for both parties to a contract (i.e., lessees and lessors). The new standard requires lessees to apply a dual approach, classifying leases as either finance or operating leases based on the principle of whether or not the lease is effectively a financed purchase by the lessee. This classification will determine whether lease expense is recognized based on an effective interest method or on a straight-line basis over the term of the lease. A lessee is also required to record a right-of-use asset and a lease liability for all leases with a term of greater than 12 months regardless of their classification. Accounting for leases with a term of 12 months or less will be similar to existing guidance for operating leases today. The new standard requires lessors to account for leases using an approach that is substantially equivalent to existing guidance for sales-type leases, direct financing leases and operating leases. ASU No. 2016-02 is expected to impact the Company’s consolidated financial statements for leases where the Company is a lessee, primarily for the Company’s data center operating leases, ground leases and administrative office leases, and the Company will be required to record a lease liability and a right of use asset on its condensed consolidated balance sheet at fair value upon adoption. ASU No. 2016-02 also limits the capitalization of leasing costs to initial direct costs, which will likely result in a reduction to our capitalized leasing costs and an increase in expenses, though the amount of such change is highly dependent upon the leasing compensation structures in place at the time of adoption. ASU No. 2016-02 supersedes the previous leases standard, Leases (Topic 840). The standard is effective on January 1, 2019, with early adoption permitted. The new leasing standard requires modified retrospective transition. In March 2018, the FASB affirmed a proposed ASU that would allow entities to elect a simplified transition approach which would require applying the provisions of the new guidance at the effective date as opposed to the earliest period presented under the modified retrospective approach. A set of practical expedients for implementation, which must be elected as a package and for all leases, may also be elected. These practical expedients include relief from re-assessing lease classification at the adoption date for expired or existing leases, although a right-of-use asset and lease liability would still be recorded for such leases. In March 2018, the FASB affirmed a proposed ASU that would include creating a practical expedient that would provide lessors an option not to separate lease and non-lease components when certain criteria are met and instead account for those components as a single component. In July 2018, the FASB issued ASU No. 2018-11, “Leases (Topic 842): Targeted Improvements.” This ASU permits an entity to elect an additional transition method to the existing modified retrospective transition requirements. Under the new transition method, an entity could adopt the provisions of ASU No. 2016-02 by recognizing a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption without adjustment to the financial statements for periods prior to adoption. Consequently, an entity’s reporting for the comparative periods presented in the financial statements in which it adopts the new leases standard will continue to be in accordance with the previous lease guidance in Topic 840. We are in the process of finalizing our review of our lease agreements in light of Topic 842 guidance, implementing a financial lease accounting system, evaluating internal control changes to support management in the accounting for and disclosure of leasing activities, and assessing available transition practical expedients. While we are still in the process of completing our implementation evaluation of ASU No. 2016-02, we currently believe the most significant changes to our financial statements relate to the recognition of a lease liability and offsetting right-of-use asset in our consolidated balance sheet for operating leases. ASU No. 2016-02 will be effective for us as of January 1, 2019. In January 2017, the FASB issued guidance codified in ASU No. 2017-04, "Intangibles – Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment". ASU No. 2017-04 simplifies the accounting for goodwill impairment by eliminating the process of measuring the implied value of goodwill, known as step two, from the goodwill impairment test. Instead, if the carrying amount of a reporting unit exceeds its fair value, an impairment loss shall be recognized in an amount equal to that excess, limited to the total amount of goodwill allocated to that reporting unit. The standard will be effective for interim and annual reporting periods beginning after December 15, 2019, with early adoption permitted. We do not expect the provisions of ASU No. 2017-04 to have a material impact on our consolidated financial statements. In June 2018, the FASB issued ASU No. 2018-07, “Improvements to Nonemployee Share-Based Payment Accounting,” which more closely aligns the accounting for employee and nonemployee share-based payments. The standard will be effective for interim and annual reporting periods beginning after December 15, 2018. Early adoption is permitted, but no earlier than an entity’s adoption date of Topic 606. We do not expect the provisions of ASU No. 2018-07 to have a material impact on our consolidated financial statements. In August 2018, the FASB issued ASU No. 2018-13, “Fair Value Measurement (Topic 820): Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement.” This ASU amends existing fair value measurement disclosure requirements by adding, changing, or removing certain disclosures. ASU No. 2018-13 will be effective for us as of January 1, 2020, and earlier adoption is permitted. We are currently reviewing the impact this ASU will have on our financial statements.

Organization and Description _2

Organization and Description of Business (Tables)	9 Months Ended
	Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Real Estate Properties	A summary of our data center portfolio as of September 30, 2018 and December 31, 2017 is as follows: Data Centers As of September 30, 2018 As of December 31, 2017 Region Operating Held for Sale Unconsolidated Joint Ventures Total Operating Held for Sale Unconsolidated Joint Ventures Total United States 131 — 14 145 131 7 14 152 Europe 38 — — 38 38 — — 38 Asia 3 — 4 7 3 — 4 7 Australia 5 — — 5 5 — — 5 Canada 3 — — 3 3 — — 3 Total 180 — 18 198 180 7 18 205

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2018
Accounting Policies [Abstract]
Schedule of Goodwill	The following is a summary of goodwill activity for the nine months ended September 30, 2018 (in thousands): Balance as of December 31, 2017 Impact of Change in Foreign Exchange Rates Balance as of September 30, 2018 Merger / Portfolio Acquisition Telx Acquisition $ 330,845 $ — $ 330,845 European Portfolio Acquisition 466,604 (16,253 ) 450,351 DuPont Fab ros Technology Merger 2,592,146 — 2,592,146 Total $ 3,389,595 $ (16,253 ) $ 3,373,342

Investments in Real Estate (Tab

Investments in Real Estate (Tables)	9 Months Ended
	Sep. 30, 2018
Real Estate [Abstract]
Schedule of Properties Acquired	We acquired the following real estate during the nine months ended September 30, 2018 : Location Market Date Acquired Amount (in millions) 10000-10006 Godwin Drive (1) Northern Virginia May 3, 2018 $ 16.5 2825-2845 Lafayette Street Silicon Valley Jun 19, 2018 55.5 9905 Godwin Drive (1) Northern Virginia Jul 11, 2018 5.8 Pacific Boulevard and S. Sterling Boulevard Northern Virginia Jul 17, 2018 26.8 160 Lockwood Road (1)(2) Sydney Sep 7, 2018 7.7 $ 112.3 (1) Represents currently vacant land which is not included in our operating property count. Purchase price excludes capitalized closing costs. (2) Purchase price in U.S. dollars.
Schedule of Properties Sold	We sold the following real estate properties during the nine months ended September 30, 2018 : Location Metro Area Date Sold Gross Proceeds (in millions) Gain (loss) on sale (in millions) 200 Quannapowitt Parkway Boston Jan 25, 2018 $ 15.0 $ (0.4 ) 34551 Ardenwood Boulevard Silicon Valley Feb 9, 2018 73.3 25.3 3065 Gold Camp Drive Sacramento Mar 14, 2018 14.2 5.4 11085 Sun Center Drive Sacramento Mar 14, 2018 36.8 9.1 Austin Portfolio Austin Apr 19, 2018 47.6 12.0 2010 East Centennial Circle Phoenix May 22, 2018 5.5 (0.5 ) 1125 Energy Park Drive Minneapolis May 31, 2018 7.0 2.8 360 Spear Street San Francisco Sep 21, 2018 92.3 26.7 $ 291.7 $ 80.4

Investments in Unconsolidated_2

Investments in Unconsolidated Joint Ventures (Tables)	9 Months Ended
	Sep. 30, 2018
Equity Method Investments and Joint Ventures [Abstract]
Summary of Financial Information for Joint Ventures	The following tables present summarized financial information for our material joint ventures as of September 30, 2018 and December 31, 2017 and for the nine months ended September 30, 2018 and 2017 (in thousands): As of September 30, 2018 Nine Months Ended September 30, 2018 2018 Net Investment in Properties Total Assets Debt Total Liabilities Equity Revenues Property Operating Expense Net Operating Income Net Income Total Unconsolidated Joint Ventures $ 1,045,943 $ 1,338,295 $ 719,801 $ 847,814 $ 490,481 $ 159,336 $ (56,603 ) $ 102,733 $ 31,193 Our investment in and share of equity in earnings of unconsolidated joint ventures $ 169,919 $ 23,734 As of December 31, 2017 Nine Months Ended September 30, 2017 2017 Net Investment in Properties Total Assets Debt Total Liabilities Equity Revenues Property Operating Expense Net Operating Income Net Income Total Unconsolidated Joint Ventures $ 1,061,950 $ 1,375,006 $ 712,690 $ 869,879 $ 505,127 $ 106,793 $ (32,869 ) $ 73,924 $ 32,545 Our investment in and share of equity in earnings of unconsolidated joint ventures $ 163,477 $ 19,592

Acquired Intangible Assets an_2

Acquired Intangible Assets and Liabilities (Tables)	9 Months Ended
	Sep. 30, 2018
Acquired Intangible Assets And Liabilities [Abstract]
Summary of Acquired Intangible Assets	The following summarizes our acquired intangible assets (real estate intangibles, comprised of acquired in-place lease value and tenant relationship value along with acquired above-market lease value) and intangible liabilities (acquired below-market lease value) as of September 30, 2018 and December 31, 2017 . Balance as of (Amounts in thousands) September 30, 2018 December 31, 2017 Real Estate Intangibles: Acquired in-place lease value: Gross amount $ 1,452,050 $ 1,473,515 Accumulated amortization (748,087 ) (613,948 ) Net $ 703,963 $ 859,567 Tenant relationship value: Gross amount $ 1,969,111 $ 1,978,277 Accumulated amortization (261,618 ) (169,919 ) Net $ 1,707,493 $ 1,808,358 Acquired above-market leases: Gross amount $ 280,399 $ 294,514 Accumulated amortization (145,272 ) (110,139 ) Net $ 135,127 $ 184,375 Acquired below-market leases: Gross amount $ 443,457 $ 469,119 Accumulated amortization (235,255 ) (219,654 ) Net $ 208,202 $ 249,465
Schedule of Estimated Annual Amortization of Below Market Leases	Estimated annual amortization of acquired below-market leases, net of acquired above-market leases, for each of the five succeeding years and thereafter, commencing October 1, 2018 is as follows: (Amounts in thousands) Remainder of 2018 $ (6,690 ) 2019 (16,127 ) 2020 (3,902 ) 2021 899 2022 7,932 Thereafter 90,963 Total $ 73,075
Schedule of Estimated Annual Amortization of Acquired of Intangible Assets	Estimated annual amortization of tenant relationship value for each of the five succeeding years and thereafter, commencing October 1, 2018 is as follows: (Amounts in thousands) Remainder of 2018 $ 30,808 2019 123,232 2020 123,232 2021 123,232 2022 123,232 Thereafter 1,183,757 Total $ 1,707,493 Estimated annual amortization of acquired in-place lease value for each of the five succeeding years and thereafter, commencing October 1, 2018 is as follows: (Amounts in thousands) Remainder of 2018 $ 47,782 2019 147,470 2020 111,611 2021 87,059 2022 65,179 Thereafter 244,862 Total $ 703,963

Debt of the Operating Partner_2

Debt of the Operating Partnership (Tables) - Digital Realty Trust, L.P.	9 Months Ended
	Sep. 30, 2018
Debt Instrument [Line Items]
Summary of Outstanding Indebtedness of the Operating Partnership	A summary of outstanding indebtedness of the Operating Partnership as of September 30, 2018 and December 31, 2017 is as follows (in thousands): Indebtedness Interest Rate at September 30, 2018 Maturity Date Principal Outstanding at September 30, 2018 Principal Outstanding at December 31, 2017 Global revolving credit facility Various (1) Jan 15, 2020 $ 594,983 (2) $ 558,191 (2) Deferred financing costs, net (4,694 ) (7,245 ) Global revolving credit facility, net 590,289 550,946 Unsecured Term Loans Unsecured term loan — 5-year Various (3)(4) Jan 15, 2021 1,056,702 (5) 1,125,117 (5) Unsecured term loan — 7-year Various (3)(4) Jan 15, 2023 300,000 (5) 300,000 (5) Deferred financing costs, net (3,733 ) (4,784 ) Unsecured term loan, net 1,352,969 1,420,333 Floating rate notes due 2019 EURIBOR + 0.500% May 22, 2019 145,050 (6) 150,063 (6) 5.875% notes due 2020 5.875% Feb 1, 2020 500,000 500,000 3.400% notes due 2020 3.400% Oct 1, 2020 500,000 500,000 5.250% notes due 2021 5.250% Mar 15, 2021 400,000 400,000 3.950% notes due 2022 3.950% Jul 1, 2022 500,000 500,000 3.625% notes due 2022 3.625% Oct 1, 2022 300,000 300,000 2.750% notes due 2023 2.750% Feb 1, 2023 350,000 350,000 4.750% notes due 2023 4.750% Oct 13, 2023 390,930 (7) 405,390 (7) 2.625% notes due 2024 2.625% Apr 15, 2024 696,240 (6) 720,300 (6) 2.750% notes due 2024 2.750% Jul 19, 2024 325,775 (7) 337,825 (7) 4.250% notes due 2025 4.250% Jan 17, 2025 521,240 (7) 540,520 (7) 4.750% notes due 2025 4.750% Oct 1, 2025 450,000 450,000 3.700% notes due 2027 3.700% Aug 15, 2027 1,000,000 1,000,000 4.450% notes due 2028 4.450% Jul 15, 2028 650,000 — 3.300% notes due 2029 3.300% Jul 19, 2029 456,085 (7) 472,955 (7) Unamortized discounts (16,495 ) (18,508 ) Total senior notes, net of discount 7,168,825 6,608,545 Deferred financing costs, net (38,284 ) (37,788 ) Total unsecured senior notes, net of discount and deferred financing costs 7,130,541 6,570,757 Indebtedness Interest Rate at September 30, 2018 Maturity Date Principal Outstanding September 30, 2018 Principal Outstanding December 31, 2017 Mortgage loans: 731 East Trade Street 8.22% Jul 1, 2020 $ 1,930 $ 2,370 Secured note due 2023 LIBOR + 1.100% (4) Mar 1, 2023 104,000 104,000 Unamortized net premiums 171 241 Total mortgage loans, including premiums 106,101 106,611 Deferred financing costs, net (29 ) (29 ) Total mortgage loans, including premiums and net of deferred financing costs 106,072 106,582 Total indebtedness $ 9,179,871 $ 8,648,618 _________________________________ (1) The interest rate for borrowings under the global revolving credit facility equals the applicable index plus a margin of 100 basis points, which is based on the current credit ratings of our long-term debt. An annual facility fee of 20 basis points, which is based on the credit ratings of our long-term debt, is due and payable quarterly on the total commitment amount of the facility. Two six -month extensions are available, which we may exercise if certain conditions are met. (2) Balances as of September 30, 2018 and December 31, 2017 are as follows (balances, in thousands): Denomination of Draw Balance as of September 30, 2018 Weighted-average interest rate Balance as of December 31, 2017 Weighted-average interest rate Floating Rate Borrowing (a) U.S. dollar ($) $ 240,000 3.23 % $ 400,000 2.48 % British pound sterling (£) — — % 18,918 (d) 1.50 % Euro (€) 74,846 (c) 0.62 % 31,213 (d) 0.62 % Australian dollar (AUD) 58,659 (c) 2.85 % — — % Hong Kong dollar (HKD) 7,779 (c) 2.91 % 4,100 (d) 2.20 % Japanese yen (JPY) 116,195 (c) 0.90 % 65,890 (d) 0.96 % Singapore dollar (SGD) 25,114 (c) 2.61 % — — % Canadian dollar (CAD) 67,390 (c) 2.82 % 23,070 (d) 2.36 % Total $ 589,983 2.32 % $ 543,191 2.15 % Base Rate Borrowing (b) U.S. dollar ($) $ 5,000 5.25 % $ 15,000 4.50 % Total borrowings $ 594,983 2.35 % $ 558,191 2.21 % (a) The interest rates for floating rate borrowings under the global revolving credit facility equal the applicable index plus a margin of 100 basis points, which is based on the credit ratings of our long-term debt. (b) The interest rates for base rate borrowings under the global revolving credit facility equal the U.S. Prime Rate. (c) Based on exchange rates of $1.16 to €1.00, $0.72 to 1.00 AUD, $0.13 to 1.00 HKD, $0.01 to 1.00 JPY, $0.73 to 1.00 SGD and $0.77 to 1.00 CAD, respectively, as of September 30, 2018 . (d) Based on exchange rates of $1.35 to £1.00, $1.20 to €1.00, $0.13 to 1.00 HKD, $0.01 to 1.00 JPY and $0.80 to 1.00 CAD, respectively, as of December 31, 2017 . (3) Interest rates are based on our current senior unsecured debt ratings and are 110 basis points and 155 basis points over the applicable index for floating rate advances for the 5 -Year Term Loan and the 7 -Year Term Loan, respectively. (4) We have entered into interest rate swap agreements as a cash flow hedge for interest generated by the U.S. dollar, British pound sterling and Canadian dollar tranches of the unsecured term loans and the secured note due 2023. See Note 14 "Derivative Instruments" for further information. (5) Balances as of September 30, 2018 and December 31, 2017 are as follows (balances, in thousands): Denomination of Draw Balance as of September 30, 2018 Weighted-average interest rate Balance as of December 31, 2017 Weighted-average interest rate U.S. dollar ($) $ 606,911 3.47 % (b) $ 606,911 2.78 % (d) British pound sterling (£) 220,843 (a) 1.82 % (b) 229,011 (c) 1.59 % (d) Singapore dollar (SGD) 189,713 (a) 2.68 % 233,788 (c) 2.17 % Australian dollar (AUD) 166,369 (a) 2.94 % 179,841 (c) 2.79 % Hong Kong dollar (HKD) 85,221 (a) 2.80 % 85,762 (c) 2.20 % Canadian dollar (CAD) 76,298 (a) 2.93 % (b) 78,357 (c) 2.44 % (d) Japanese yen (JPY) 11,347 (a) 1.01 % 11,447 (c) 1.05 % Total $ 1,356,702 2.94 % (b) $ 1,425,117 2.42 % (d) (a) Based on exchange rates of $1.30 to £1.00, $0.73 to 1.00 SGD, $0.72 to 1.00 AUD, $0.13 to 1.00 HKD, $0.77 to 1.00 CAD and $0.01 to 1.00 JPY, respectively, as of September 30, 2018 . (b) As of September 30, 2018 , the weighted-average interest rate reflecting interest rate swaps was 2.72% (U.S. dollar), 1.89% (British pound sterling), 1.88% (Canadian dollar) and 2.55% (Total). See Note 14 "Derivative Instruments" for further discussion on interest rate swaps. (c) Based on exchange rates of $1.35 to £1.00, $0.75 to 1.00 SGD, $0.78 to 1.00 AUD, $0.13 to 1.00 HKD, $0.80 to 1.00 CAD and $0.01 to 1.00 JPY, respectively, as of December 31, 2017 . (d) As of December 31, 2017 , the weighted-average interest rate reflecting interest rate swaps was 2.72% (U.S. dollar), 1.89% (British pound sterling), 1.88% (Canadian dollar) and 2.41% (Total). (6) Based on exchange rates of $1.16 to €1.00 as of September 30, 2018 and $1.20 to €1.00 as of December 31, 2017 . (7) Based on exchange rates of $1.30 to £1.00 as of September 30, 2018 and $1.35 to £1.00 as of December 31, 2017 .
Schedule of Debt Maturities and Principal Maturities	The table below summarizes our debt maturities and principal payments as of September 30, 2018 (in thousands): Global Revolving Credit Facility (1) Unsecured Unsecured Senior Notes Mortgage Loans Total Debt Remainder of 2018 $ — $ — $ — $ 153 $ 153 2019 — — 145,050 644 145,694 2020 594,983 — 1,000,000 1,133 1,596,116 2021 — 1,056,702 400,000 — 1,456,702 2022 — — 800,000 — 800,000 Thereafter — 300,000 4,840,270 104,000 5,244,270 Subtotal $ 594,983 $ 1,356,702 $ 7,185,320 $ 105,930 $ 9,242,935 Unamortized discount — — (16,495 ) — (16,495 ) Unamortized premium — — — 171 171 Total $ 594,983 $ 1,356,702 $ 7,168,825 $ 106,101 $ 9,226,611 (1) Subject to two six -month extension options exercisable by us. The bank group is obligated to grant the extension options provided we give proper notice, we make certain representations and warranties and no default exists under the global revolving credit facility.

Income per Share (Tables)

Income per Share (Tables)	9 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Summary of Basic and Diluted Earnings Per Share	The following is a summary of basic and diluted income per share (in thousands, except share and per share amounts): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Net income (loss) available to common stockholders $ 67,268 $ (4,140 ) $ 218,700 $ 119,842 Weighted average shares outstanding—basic 206,118,472 170,194,254 205,931,031 163,481,306 Potentially dilutive common shares: Unvested incentive units 169,100 — 160,117 150,369 Forward equity offering 37,884 — 1,847 166,493 Market performance-based awards 440,800 — 462,632 572,928 Weighted average shares outstanding—diluted 206,766,256 170,194,254 206,555,627 164,371,096 Income (loss) per share: Basic $ 0.33 $ (0.02 ) $ 1.06 $ 0.73 Diluted $ 0.33 $ (0.02 ) $ 1.06 $ 0.73
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	We have excluded the following potentially dilutive securities in the calculations above as they would be antidilutive or not dilutive: Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Weighted average of Operating Partnership common units not owned by Digital Realty Trust, Inc. 8,170,912 3,266,451 8,268,382 2,566,766 Potentially dilutive Series C Cumulative Redeemable Perpetual Preferred Stock 1,727,724 329,709 1,864,489 109,903 Potentially dilutive Series F Cumulative Redeemable Preferred Stock — — — 617,734 Potentially dilutive Series G Cumulative Redeemable Preferred Stock 2,142,282 2,193,331 2,311,864 2,262,875 Potentially dilutive Series H Cumulative Redeemable Preferred Stock 3,139,291 3,214,098 3,387,795 3,316,008 Potentially dilutive Series I Cumulative Redeemable Preferred Stock 2,144,789 2,195,898 2,314,569 2,265,524 Potentially dilutive Series J Cumulative Redeemable Preferred Stock 1,711,186 1,045,730 1,846,643 348,577 Total 19,036,184 12,245,217 19,993,742 11,487,387

Income per Unit (Tables)

Income per Unit (Tables)	9 Months Ended
	Sep. 30, 2018
Class of Stock [Line Items]
Summary of Basic and Diluted Earnings Per Share	The following is a summary of basic and diluted income per share (in thousands, except share and per share amounts): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Net income (loss) available to common stockholders $ 67,268 $ (4,140 ) $ 218,700 $ 119,842 Weighted average shares outstanding—basic 206,118,472 170,194,254 205,931,031 163,481,306 Potentially dilutive common shares: Unvested incentive units 169,100 — 160,117 150,369 Forward equity offering 37,884 — 1,847 166,493 Market performance-based awards 440,800 — 462,632 572,928 Weighted average shares outstanding—diluted 206,766,256 170,194,254 206,555,627 164,371,096 Income (loss) per share: Basic $ 0.33 $ (0.02 ) $ 1.06 $ 0.73 Diluted $ 0.33 $ (0.02 ) $ 1.06 $ 0.73
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	We have excluded the following potentially dilutive securities in the calculations above as they would be antidilutive or not dilutive: Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Weighted average of Operating Partnership common units not owned by Digital Realty Trust, Inc. 8,170,912 3,266,451 8,268,382 2,566,766 Potentially dilutive Series C Cumulative Redeemable Perpetual Preferred Stock 1,727,724 329,709 1,864,489 109,903 Potentially dilutive Series F Cumulative Redeemable Preferred Stock — — — 617,734 Potentially dilutive Series G Cumulative Redeemable Preferred Stock 2,142,282 2,193,331 2,311,864 2,262,875 Potentially dilutive Series H Cumulative Redeemable Preferred Stock 3,139,291 3,214,098 3,387,795 3,316,008 Potentially dilutive Series I Cumulative Redeemable Preferred Stock 2,144,789 2,195,898 2,314,569 2,265,524 Potentially dilutive Series J Cumulative Redeemable Preferred Stock 1,711,186 1,045,730 1,846,643 348,577 Total 19,036,184 12,245,217 19,993,742 11,487,387
Digital Realty Trust, L.P.
Class of Stock [Line Items]
Summary of Basic and Diluted Earnings Per Share	The following is a summary of basic and diluted income per unit (in thousands, except unit and per unit amounts): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Net income (loss) available to common unitholders $ 69,968 $ (4,219 ) $ 227,580 $ 121,474 Weighted average units outstanding—basic 214,289,384 173,460,704 214,199,414 166,048,072 Potentially dilutive common units: Unvested incentive units 169,100 — 160,117 166,493 Forward equity offering 37,884 — 1,847 150,369 Market performance-based awards 440,800 — 462,632 572,928 Weighted average units outstanding—diluted 214,937,168 173,460,704 214,824,010 166,937,862 Income (loss) per unit: Basic $ 0.33 $ (0.02 ) $ 1.06 $ 0.73 Diluted $ 0.33 $ (0.02 ) $ 1.06 $ 0.73
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	We have excluded the following potentially dilutive securities in the calculations above as they would be antidilutive or not dilutive: Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Potentially dilutive Series C Cumulative Redeemable Perpetual Preferred Units 1,727,724 329,709 1,864,489 109,903 Potentially dilutive Series F Cumulative Redeemable Preferred Units — — — 617,734 Potentially dilutive Series G Cumulative Redeemable Preferred Units 2,142,282 2,193,331 2,311,864 2,262,875 Potentially dilutive Series H Cumulative Redeemable Preferred Units 3,139,291 3,214,098 3,387,795 3,316,008 Potentially dilutive Series I Cumulative Redeemable Preferred Units 2,144,789 2,195,898 2,314,569 2,265,524 Potentially dilutive Series J Cumulative Redeemable Preferred Units 1,711,186 1,045,730 1,846,643 348,577 Total 10,865,272 8,978,766 11,725,360 8,920,621

Equity and Accumulated Other _2

Equity and Accumulated Other Comprehensive Loss, Net (Tables)	9 Months Ended
	Sep. 30, 2018
Equity [Abstract]
Ownership Interest In The Operating Partnership	The following table shows the ownership interests in the Operating Partnership as of September 30, 2018 and December 31, 2017 : September 30, 2018 December 31, 2017 Number of units Percentage of total Number of units Percentage of total Digital Realty Trust, Inc. 206,267,055 96.1 % 205,470,300 96.0 % Noncontrolling interests consist of: Common units held by third parties 6,411,484 3.0 % 6,899,094 3.2 % Incentive units held by employees and directors (see Note 14) 1,929,103 0.9 % 1,590,001 0.8 % 214,607,642 100.0 % 213,959,395 100.0 %
Summary of Activity for Noncontrolling Interests in the Operating Partnership	The following table shows activity for the noncontrolling interests in the Operating Partnership for the nine months ended September 30, 2018 : Common Units Incentive Units Total As of December 31, 2017 6,899,094 1,590,001 8,489,095 Redemption of common units for shares of Digital Realty Trust, Inc. common stock (1) (487,610 ) — (487,610 ) Conversion of incentive units held by employees and directors for shares of Digital Realty Trust, Inc. common stock (1) — (80,182 ) (80,182 ) Incentive units issued upon achievement of market performance condition — 326,947 326,947 Grant of incentive units to employees and directors — 114,472 114,472 Cancellation / forfeitures of incentive units held by employees and directors — (22,135 ) (22,135 ) As of September 30, 2018 6,411,484 1,929,103 8,340,587 (1) Redemption of common units were recorded as a reduction to noncontrolling interests in the Operating Partnership and an increase to common stock and additional paid in capital based on the book value per unit in the accompanying condensed consolidated balance sheet of Digital Realty Trust, Inc.
Schedule of Dividends	We have declared and paid the following dividends on our common and preferred stock for the nine months ended September 30, 2018 (in thousands, except per share data): Date dividend declared Dividend Series C Preferred Stock Series G Preferred Stock Series H Preferred Stock Series I Preferred Stock Series J Preferred Stock Common March 1, 2018 March 30, 2018 $ 3,333 $ 3,672 $ 6,730 $ 3,969 $ 2,625 $ 208,015 May 8, 2018 June 29, 2018 3,333 3,672 6,730 3,969 2,625 208,071 August 14, 2018 September 28, 2018 3,333 3,672 6,730 3,969 2,625 208,166 $ 9,999 $ 11,016 $ 20,190 $ 11,907 $ 7,875 $ 624,252 Annual rate of dividend per share $ 1.65625 $ 1.46875 $ 1.84375 $ 1.58750 $ 1.31250 $ 4.04000
Schedule of Accumulated Other Comprehensive Income, Net	The accumulated balances for each item within other comprehensive income (loss), net are as follows (in thousands): Foreign currency Cash flow hedge Foreign currency net investment hedge adjustments Accumulated other Balance as of December 31, 2017 $ (147,370 ) $ 13,200 $ 25,738 $ (108,432 ) Net current period change (8,272 ) 15,705 — 7,433 Reclassification to interest expense from interest — (2,202 ) — (2,202 ) Balance as of September 30, 2018 $ (155,642 ) $ 26,703 $ 25,738 $ (103,201 )

Capital and Accumulated Other_2

Capital and Accumulated Other Comprehensive Loss (Tables)	9 Months Ended
	Sep. 30, 2018
Class of Stock [Line Items]
Schedule of Distributions	We have declared and paid the following dividends on our common and preferred stock for the nine months ended September 30, 2018 (in thousands, except per share data): Date dividend declared Dividend Series C Preferred Stock Series G Preferred Stock Series H Preferred Stock Series I Preferred Stock Series J Preferred Stock Common March 1, 2018 March 30, 2018 $ 3,333 $ 3,672 $ 6,730 $ 3,969 $ 2,625 $ 208,015 May 8, 2018 June 29, 2018 3,333 3,672 6,730 3,969 2,625 208,071 August 14, 2018 September 28, 2018 3,333 3,672 6,730 3,969 2,625 208,166 $ 9,999 $ 11,016 $ 20,190 $ 11,907 $ 7,875 $ 624,252 Annual rate of dividend per share $ 1.65625 $ 1.46875 $ 1.84375 $ 1.58750 $ 1.31250 $ 4.04000
Schedule of Accumulated Other Comprehensive Income, Net	The accumulated balances for each item within other comprehensive income (loss), net are as follows (in thousands): Foreign currency Cash flow hedge Foreign currency net investment hedge adjustments Accumulated other Balance as of December 31, 2017 $ (147,370 ) $ 13,200 $ 25,738 $ (108,432 ) Net current period change (8,272 ) 15,705 — 7,433 Reclassification to interest expense from interest — (2,202 ) — (2,202 ) Balance as of September 30, 2018 $ (155,642 ) $ 26,703 $ 25,738 $ (103,201 )
Digital Realty Trust, L.P.
Class of Stock [Line Items]
Schedule of Distributions	The Operating Partnership has declared and paid the following distributions on its common and preferred units for the nine months ended September 30, 2018 (in thousands, except for per unit data): Date distribution declared Distribution Series C Preferred Units Series G Preferred Units Series H Preferred Units Series I Preferred Units Series J Preferred Units Common March 1, 2018 March 30, 2018 $ 3,333 $ 3,672 $ 6,730 $ 3,969 $ 2,625 $ 216,953 May 8, 2018 June 29, 2018 3,333 3,672 6,730 3,969 2,625 216,789 August 14, 2018 September 28, 2018 3,333 3,672 6,730 3,969 2,625 216,825 $ 9,999 $ 11,016 $ 20,190 $ 11,907 $ 7,875 $ 650,567 Annual rate of distribution per unit $ 1.65625 $ 1.46875 $ 1.84375 $ 1.58750 $ 1.31250 $ 4.04000
Schedule of Accumulated Other Comprehensive Income, Net	The accumulated balances for each item within other comprehensive income are as follows (in thousands): Foreign currency Cash flow hedge Foreign currency net investment hedge adjustments Accumulated other Balance as of December 31, 2017 $ (151,795 ) $ 12,758 $ 26,152 $ (112,885 ) Net current period change (8,608 ) 16,336 — 7,728 Reclassification to interest expense from interest rate swaps — (2,289 ) — (2,289 ) Balance as of September 30, 2018 $ (160,403 ) $ 26,805 $ 26,152 $ (107,446 )

Incentive Plan (Tables)

Incentive Plan (Tables)	9 Months Ended
	Sep. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Deferred Compensation	Below is a summary of our compensation expense for the three and nine months ended September 30, 2018 and 2017 and our unearned compensation as of September 30, 2018 and December 31, 2017 (in millions): Deferred Compensation Unearned Compensation Expected period to recognize unearned compensation (in years) Expensed Capitalized As of September 30, 2018 As of December 31, 2017 Three Months Ended September 30, Type of incentive award 2018 2017 2018 2017 Long-term incentive units $ 1.2 $ 0.8 $ 0.1 $ 0.6 $ 11.0 $ 6.9 3.0 Market performance-based awards 3.1 2.7 0.3 0.6 28.4 24.7 2.1 Restricted stock 1.5 1.1 1.1 0.8 23.4 17.5 2.8 Nine Months Ended September 30, 2018 2017 2018 2017 Long-term incentive units $ 5.2 $ 3.4 $ 0.2 $ 1.4 Market performance-based awards 10.0 7.3 0.7 1.9 Restricted stock 4.7 3.3 3.2 2.5
Summary of Long-Term Incentive Unit Activity	Below is a summary of our long-term incentive unit activity for the nine months ended September 30, 2018 . Unvested Long-term Incentive Units Units Weighted-Average Grant Date Fair Value Unvested, beginning of period 99,295 $ 90.59 Granted 114,472 101.26 Vested (49,054 ) 88.97 Cancelled or expired (14,275 ) 82.85 Unvested, end of period 150,438 $ 99.49
Market Performance Based Awards	In the event that the RMS Relative Market Performance during the Market Performance Period is achieved at the “threshold,” “target” or “high” level as set forth below, the awards will become vested as to the market condition with respect to the percentage of Class D units or RSUs, as applicable, set forth below: Level RMS Relative Market Performance Vesting Percentage Below Threshold Level ≤ -300 basis points 0% Threshold Level -300 basis points 25% Target Level 100 basis points 50% High Level > 500 basis points 100%
Schedule Of Valuation Assumptions	Assumptions used in the valuations are summarized as follows: Award Date Expected Stock Price Volatility Risk-Free Interest rate January 1, 2017 25% 1.49% February 28, 2017 23% 1.43% January 1, 2018 22% 1.98% March 1, 2018 22% 2.34% March 9, 2018 22% 2.42%
Summary of Restricted Stock Activity	Below is a summary of our restricted stock activity for the nine months ended September 30, 2018 . Unvested Restricted Stock Shares Weighted-Average Grant Date Fair Value Unvested, beginning of period 259,422 $ 90.54 Granted 164,748 101.24 Vested (92,432 ) 82.96 Cancelled or expired (28,510 ) 96.69 Unvested, end of period 303,228 $ 97.21

Derivative Instruments (Tables)

Derivative Instruments (Tables)	9 Months Ended
	Sep. 30, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Outstanding Derivative Instruments	As of September 30, 2018 and December 31, 2017 , we had the following outstanding interest rate derivatives that were designated as effective cash flow hedges of interest rate risk (in thousands): Notional Amount Fair Value at Significant Other As of September 30, 2018 As of December 31, 2017 Type of Strike Effective Date Expiration Date As of September 30, 2018 (5) As of December 31, 2017 (5) Currently-paying contracts $ 206,000 (1) $ 206,000 (1) Swap 1.611 Jun 15, 2017 Jan 15, 2020 $ 2,856 $ 1,409 54,905 (1) 54,905 (1) Swap 1.605 Jun 6, 2017 Jan 6, 2020 747 374 75,000 (1) 75,000 (1) Swap 1.016 Apr 6, 2016 Jan 6, 2021 3,023 2,260 75,000 (1) 75,000 (1) Swap 1.164 Jan 15, 2016 Jan 15, 2021 2,808 1,947 300,000 (2) 300,000 (2) Swap 1.435 Jan 15, 2016 Jan 15, 2023 17,829 9,978 220,843 (3) 229,012 (3) Swap 0.792 Jan 15, 2016 Jan 15, 2019 (24 ) (430 ) 76,298 (4) 78,357 (4) Swap 0.779 Jan 15, 2016 Jan 15, 2021 2,960 3,034 $ 1,008,046 $ 1,018,274 $ 30,199 $ 18,572 (1) Represents portions of the U.S. dollar tranche of the 5 -Year Term Loan. (2) Represents the U.S. dollar tranche of the 7 -Year Term Loan. (3) Represents the British pound sterling tranche of the 5 -Year Term Loan. Translation to U.S. dollars is based on exchange rates of $1.30 to £1.00 as of September 30, 2018 and $1.35 to £1.00 as of December 31, 2017 . (4) Represents the Canadian dollar tranche of the 5 -Year Term Loan. Translation to U.S. dollars is based on exchange rates of $0.77 to 1.00 CAD as of September 30, 2018 and $0.80 to 1.00 CAD as of December 31, 2017 . (5) Balance recorded in other assets in the consolidated balance sheets if positive and recorded in accounts payable and other accrued liabilities in the consolidated balance sheets if negative.

Fair Value of Financial Instr_2

Fair Value of Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2018
Fair Value Disclosures [Abstract]
Estimated Fair Value And Carrying Amounts	As of September 30, 2018 and December 31, 2017 , the aggregate estimated fair value and carrying value of our global revolving credit facility, unsecured term loans, unsecured senior notes and mortgage loans were as follows (in thousands): Categorization under the fair value hierarchy As of September 30, 2018 As of December 31, 2017 Estimated Fair Value Carrying Value Estimated Fair Value Carrying Value Global revolving credit facility (1)(5) Level 2 $ 594,983 $ 594,983 $ 558,191 $ 558,191 Unsecured term loans (2)(6) Level 2 1,356,702 1,356,702 1,425,117 1,425,117 Unsecured senior notes (3)(4)(7) Level 2 7,280,877 7,168,825 6,976,603 6,608,545 Mortgage loans (3)(8) Level 2 106,424 106,101 106,523 106,611 $ 9,338,986 $ 9,226,611 $ 9,066,434 $ 8,698,464 (1) The carrying value of our global revolving credit facility approximates estimated fair value, due to the variability of interest rates and the stability of our credit ratings. (2) The carrying value of our unsecured term loans approximates estimated fair value, due to the variability of interest rates and the stability of our credit ratings. (3) Valuations for our unsecured senior notes and mortgage loans are determined based on the expected future payments discounted at risk-adjusted rates. The 2019 Notes, 5.875% 2020 Notes, 3.400% 2020 Notes, 2021 Notes, 3.950% 2022 Notes, 3.625% 2022 Notes, 4.750% 2023 Notes, 2.750% 2023 Notes, 2.625% 2024 Notes, 2.750% 2024 Notes, 4.750% 2025 Notes, 4.250% 2025 Notes, 2027 Notes, 2028 Notes and 2029 Notes are valued based on quoted market prices. (4) The carrying value of the 5.875% 2020 Notes, 3.400% 2020 Notes, 2021 Notes, 3.625% 2022 Notes, 3.950% 2022 Notes, 4.750% 2023 Notes, 2.750% 2023 Notes, 2.625% 2024 Notes, 2.750% 2024 Notes, 4.250% 2025 Notes, 2027 Notes, 2028 Notes and 2029 Notes are net of discount of $16.5 million and $18.5 million in the aggregate as of September 30, 2018 and December 31, 2017 , respectively. (5) The estimated fair value and carrying value are exclusive of deferred financing costs of $4.7 million and $7.2 million as of September 30, 2018 and December 31, 2017 , respectively. (6) The estimated fair value and carrying value are exclusive of deferred financing costs of $3.7 million and $4.8 million as of September 30, 2018 and December 31, 2017 , respectively. (7) The estimated fair value and carrying value are exclusive of deferred financing costs of $38.3 million and $37.8 million as of September 30, 2018 and December 31, 2017 , respectively. (8) The estimated fair value and carrying value are exclusive of deferred financing costs of $0.0 million and $0.0 million as of September 30, 2018 and December 31, 2017 , respectively.

Organization and Description _3

Organization and Description of Business (Narrative) (Details) - property	Sep. 30, 2018	Dec. 31, 2017
Organization and Description of Business [Line Items]
Number of properties	198	205
Common Interest
Organization and Description of Business [Line Items]
Ownership percentage in the Operating Partnership	96.10%	96.00%
Preferred Interest
Organization and Description of Business [Line Items]
Ownership percentage in the Operating Partnership	100.00%	100.00%
United States
Organization and Description of Business [Line Items]
Number of properties	145	152
Europe
Organization and Description of Business [Line Items]
Number of properties	38	38
Asia
Organization and Description of Business [Line Items]
Number of properties	7	7
Australia
Organization and Description of Business [Line Items]
Number of properties	5	5
Canada
Organization and Description of Business [Line Items]
Number of properties	3	3
Operating Properties
Organization and Description of Business [Line Items]
Number of properties	180	180
Operating Properties | United States
Organization and Description of Business [Line Items]
Number of properties	131	131
Operating Properties | Europe
Organization and Description of Business [Line Items]
Number of properties	38	38
Operating Properties | Asia
Organization and Description of Business [Line Items]
Number of properties	3	3
Operating Properties | Australia
Organization and Description of Business [Line Items]
Number of properties	5	5
Operating Properties | Canada
Organization and Description of Business [Line Items]
Number of properties	3	3
Held-for-Sale Properties
Organization and Description of Business [Line Items]
Number of properties	0	7
Held-for-Sale Properties | United States
Organization and Description of Business [Line Items]
Number of properties	0	7
Held-for-Sale Properties | Europe
Organization and Description of Business [Line Items]
Number of properties	0	0
Held-for-Sale Properties | Asia
Organization and Description of Business [Line Items]
Number of properties	0	0
Held-for-Sale Properties | Australia
Organization and Description of Business [Line Items]
Number of properties	0	0
Held-for-Sale Properties | Canada
Organization and Description of Business [Line Items]
Number of properties	0	0
Unconsolidated Joint Ventures
Organization and Description of Business [Line Items]
Number of properties	18	18
Unconsolidated Joint Ventures | United States
Organization and Description of Business [Line Items]
Number of properties	14	14
Unconsolidated Joint Ventures | Europe
Organization and Description of Business [Line Items]
Number of properties	0	0
Unconsolidated Joint Ventures | Asia
Organization and Description of Business [Line Items]
Number of properties	4	4
Unconsolidated Joint Ventures | Australia
Organization and Description of Business [Line Items]
Number of properties	0	0
Unconsolidated Joint Ventures | Canada
Organization and Description of Business [Line Items]
Number of properties	0	0

Summary of Significant Accoun_4

Summary of Significant Accounting Policies (Narrative) (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2018USD ($)segment	Sep. 30, 2017USD ($)	Dec. 31, 2017USD ($)
Summary Of Significant Accounting Policies [Line Items]
Period in which short-term investment become cash equivalents			90 days
Interest capitalized	$ 9,700,000	$ 5,300,000	$ 25,300,000	$ 13,700,000
Compensation costs, leasing and construction activities	19,500,000	20,800,000	55,100,000	58,400,000
Cash flows from capitalized leasing costs			6,400,000	11,100,000
Impact of Change in Foreign Exchange Rates			(16,253,000)
Unrecognized tax benefits	0		0		$ 0
Income tax penalties and interest expense	$ 0	0	$ 0	0
Revenue recognized from applying Topic 840	97.00%
Revenue recognized from applying Topic 606			3.00%
Gross proceeds	$ 291,700,000		$ 291,700,000
Gain on sale of property			$ 80,400,000
Number of reportable segments | segment			1
Total operating revenues	768,924,000	$ 609,925,000	$ 2,268,211,000	$ 1,726,483,000
Net investments in real estate	$ 14,225,697,000		$ 14,225,697,000		$ 13,841,186,000
Sales | Geographic Concentration Risk
Summary Of Significant Accounting Policies [Line Items]
Concentration risk	9.40%	11.50%	9.80%	11.70%
Total long-lived assets
Summary Of Significant Accounting Policies [Line Items]
Concentration risk					12.10%
Total long-lived assets | Geographic Concentration Risk
Summary Of Significant Accounting Policies [Line Items]
Concentration risk			11.60%
Outside the United States
Summary Of Significant Accounting Policies [Line Items]
Total operating revenues	$ 139,700,000	$ 131,700,000	$ 421,300,000	$ 380,000,000
Net investments in real estate	3,300,000,000		3,300,000,000		$ 3,100,000,000
United States
Summary Of Significant Accounting Policies [Line Items]
Total operating revenues	629,300,000	478,200,000	1,800,000,000	1,300,000,000
Net investments in real estate	10,800,000,000		10,800,000,000		10,500,000,000
United Kingdom
Summary Of Significant Accounting Policies [Line Items]
Total operating revenues	72,600,000	$ 70,100,000	221,900,000	$ 202,800,000
Net investments in real estate	$ 1,600,000,000		$ 1,600,000,000		$ 1,700,000,000

Summary of Significant Accoun_5

Summary of Significant Accounting Policies Summary of Goodwill Activity (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2018USD ($)
Goodwill [Roll Forward]
Goodwill - Beginning Balance	$ 3,389,595
Impact of Change in Foreign Exchange Rates	(16,253)
Goodwill - Ending Balance	3,373,342
Telx Acquisition
Goodwill [Roll Forward]
Goodwill - Beginning Balance	330,845
Impact of Change in Foreign Exchange Rates	0
Goodwill - Ending Balance	330,845
European Portfolio Acquisition
Goodwill [Roll Forward]
Goodwill - Beginning Balance	466,604
Impact of Change in Foreign Exchange Rates	(16,253)
Goodwill - Ending Balance	450,351
DFT Company
Goodwill [Roll Forward]
Goodwill - Beginning Balance	2,592,146
Impact of Change in Foreign Exchange Rates	0
Goodwill - Ending Balance	$ 2,592,146

Investments in Real Estate (Sch

Investments in Real Estate (Schedule of Real Estate Property Acquisitions) (Details) $ in Thousands

Sep. 21, 2018USD ($)

Sep. 07, 2018USD ($)

Jul. 17, 2018USD ($)

Jul. 11, 2018USD ($)

Jun. 19, 2018USD ($)

May 31, 2018USD ($)

May 22, 2018USD ($)

May 03, 2018USD ($)

Apr. 19, 2018USD ($)

Mar. 14, 2018USD ($)

Feb. 09, 2018USD ($)

Jan. 25, 2018USD ($)

Sep. 30, 2018USD ($)

Jun. 30, 2018property

Dec. 31, 2017USD ($)property

Business Acquisition [Line Items]

Payment to acquire real estate

$ 112,300

Assets

21,462,110

$ 21,404,345

Liabilities

10,681,095

$ 10,300,993

Gross proceeds

291,700

Gain (loss) on sale of property

$ 80,400

Held-for-sale

Business Acquisition [Line Items]

Number of additional properties | property

4

8

Assets

$ 139,500

Liabilities

$ 5,000

200 Quannapowitt Parkway

Business Acquisition [Line Items]

Gross proceeds

$ 15,000

Gain (loss) on sale of property

$ (400)

34551 Ardenwood Boulevard

Business Acquisition [Line Items]

Gross proceeds

$ 73,300

Gain (loss) on sale of property

$ 25,300

3065 Gold Camp Drive

Business Acquisition [Line Items]

Gross proceeds

$ 14,200

Gain (loss) on sale of property

5,400

11085 Sun Center Drive

Business Acquisition [Line Items]

Gross proceeds

36,800

Gain (loss) on sale of property

$ 9,100

Austin Portfolio

Business Acquisition [Line Items]

Gross proceeds

$ 47,600

Gain (loss) on sale of property

$ 12,000

2010 East Centennial Circle

Business Acquisition [Line Items]

Gross proceeds

$ 5,500

Gain (loss) on sale of property

$ (500)

1125 Energy Park Drive

Business Acquisition [Line Items]

Gross proceeds

$ 7,000

Gain (loss) on sale of property

$ 2,800

360 Spear Street

Business Acquisition [Line Items]

Gross proceeds

$ 92,300

Gain (loss) on sale of property

$ 26,700

10000-10006 Godwin Drive

Business Acquisition [Line Items]

Payment to acquire real estate

$ 16,500

2825-2845 Lafayette Street

Business Acquisition [Line Items]

Payment to acquire real estate

$ 55,500

9905 Godwin Drive

Business Acquisition [Line Items]

Payment to acquire real estate

$ 5,800

Pacific Boulevard and S. Sterling Boulevard

Business Acquisition [Line Items]

Payment to acquire real estate

$ 26,800

160 Lockwood Road

Business Acquisition [Line Items]

Payment to acquire real estate

$ 7,700

Investments in Unconsolidated_3

Investments in Unconsolidated Joint Ventures (Narrative) (Details)	9 Months Ended
	Sep. 30, 2018propertyjoint_venture	Dec. 31, 2017property
Schedule of Equity Method Investments [Line Items]
Number of properties | property	198	205
Properties in Seattle, Hong Kong, Tokyo, Osaka
Schedule of Equity Method Investments [Line Items]
Ownership percentage in joint ventures	50.00%
Number of joint ventures | joint_venture	4
Prudential Real Estate Investors and Griffin Capital Essential Asset REIT, Inc.
Schedule of Equity Method Investments [Line Items]
Number of joint ventures | joint_venture	2
PREI
Schedule of Equity Method Investments [Line Items]
Ownership percentage in joint ventures	20.00%
Number of joint ventures | joint_venture	1
Number of properties | property	10
GCEAR
Schedule of Equity Method Investments [Line Items]
Number of properties | property	1
Property in Silicon Valley
Schedule of Equity Method Investments [Line Items]
Ownership percentage in joint ventures	17.00%

Investments in Unconsolidated_4

Investments in Unconsolidated Joint Ventures (Summary Of Financial Information For Joint Ventures) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Equity Method Investments and Joint Ventures [Abstract]
Net Investment in Properties			$ 1,045,943		$ 1,061,950
Total Assets	$ 1,338,295		1,338,295		1,375,006
Debt	719,801		719,801		712,690
Total Liabilities	847,814		847,814		869,879
Equity	490,481		490,481		505,127
Our investment in and share of equity in earnings of unconsolidated joint ventures	169,919		169,919		$ 163,477
Revenues			159,336	$ 106,793
Property Operating Expense			(56,603)	(32,869)
Net Operating Income			102,733	73,924
Net Income			31,193	32,545
Investment in and share of net income (loss)	$ 8,886	$ 5,880	$ 23,734	$ 19,592

Acquired Intangible Assets an_3

Acquired Intangible Assets and Liabilities (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Finite-Lived Intangible Assets [Line Items]
Amortization of below market leases	$ (6,800)	$ (700)	$ (20,600)	$ (4,700)
Expected average remaining lives of acquired below market leases (in years)			8 years 3 months 12 days
Amortization of acquired in-place lease value and deferred leasing costs			$ 317,355	145,262
Acquired in-place lease value
Finite-Lived Intangible Assets [Line Items]
Expected average remaining lives (in years)			6 years 2 months 2 days
Amortization of acquired in-place lease value and deferred leasing costs	50,200	20,100	$ 162,300	48,700
Weighted average remaining contractual life for acquired leases excluding renewals or extensions (in years)			5 years 8 months 4 days
Tenant relationship value
Finite-Lived Intangible Assets [Line Items]
Amortization of acquired in-place lease value and deferred leasing costs	$ 30,800	$ 19,900	$ 92,800	$ 55,000
Weighted average remaining contractual life for acquired leases excluding renewals or extensions (in years)			14 years 6 months 1 day
Acquired above-market leases
Finite-Lived Intangible Assets [Line Items]
Expected average remaining lives (in years)			3 years 11 days

Acquired Intangible Assets an_4

Acquired Intangible Assets and Liabilities (Summary of Acquired Intangible Assets) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Below-market lease, gross amount	$ 443,457	$ 469,119
Below-market lease, accumulated amortization	(235,255)	(219,654)
Total	208,202	249,465
Acquired in-place lease value
Finite-Lived Intangible Assets [Line Items]
Gross amount	1,452,050	1,473,515
Accumulated amortization	(748,087)	(613,948)
Net	703,963	859,567
Tenant relationship value
Finite-Lived Intangible Assets [Line Items]
Gross amount	1,969,111	1,978,277
Accumulated amortization	(261,618)	(169,919)
Net	1,707,493	1,808,358
Acquired above-market leases
Finite-Lived Intangible Assets [Line Items]
Gross amount	280,399	294,514
Accumulated amortization	(145,272)	(110,139)
Net	$ 135,127	$ 184,375

Acquired Intangible Assets an_5

Acquired Intangible Assets and Liabilities (Schedule of Estimated Annual Amortization of Below Market Leases) (Details) - Below-Market Leases, Net of Above-Market Leases $ in Thousands	Sep. 30, 2018USD ($)
Finite-Lived Intangible Assets [Line Items]
Remainder of 2018	$ (6,690)
2,019	(16,127)
2,020	(3,902)
2,021	899
2,022	7,932
Thereafter	90,963
Total	$ 73,075

Acquired Intangible Assets An_6

Acquired Intangible Assets And Liabilities (Schedule of Estimated Annual Amortization of Intangible Assets) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Acquired in-place lease value
Finite-Lived Intangible Assets [Line Items]
Remainder of 2018	$ 47,782
2,019	147,470
2,020	111,611
2,021	87,059
2,022	65,179
Thereafter	244,862
Net	703,963	$ 859,567
Tenant relationships
Finite-Lived Intangible Assets [Line Items]
Remainder of 2018	30,808
2,019	123,232
2,020	123,232
2,021	123,232
2,022	123,232
Thereafter	1,183,757
Net	$ 1,707,493

Debt of the Company (Narrative)

Debt of the Company (Narrative) (Details)	Sep. 30, 2018
3.400% notes due 2020
Debt Instrument [Line Items]
Stated interest rate	3.40%
3.950% notes due 2022
Debt Instrument [Line Items]
Stated interest rate	3.95%
3.625% notes due 2022
Debt Instrument [Line Items]
Stated interest rate	3.625%
4.750% notes due 2025
Debt Instrument [Line Items]
Stated interest rate	4.75%
2.750% notes due 2024
Debt Instrument [Line Items]
Stated interest rate	2.75%
2.625% notes due 2024
Debt Instrument [Line Items]
Stated interest rate	2.625%
Senior Notes | 5.875% notes due 2020
Debt Instrument [Line Items]
Stated interest rate	5.875%
Senior Notes | 3.400% notes due 2020
Debt Instrument [Line Items]
Stated interest rate	3.40%
Senior Notes | 5.250% notes due 2021
Debt Instrument [Line Items]
Stated interest rate	5.25%
Senior Notes | 3.950% notes due 2022
Debt Instrument [Line Items]
Stated interest rate	3.95%
Senior Notes | 3.625% notes due 2022
Debt Instrument [Line Items]
Stated interest rate	3.625%
Senior Notes | 2.750% notes due 2023
Debt Instrument [Line Items]
Stated interest rate	2.75%
Senior Notes | 4.750% notes due 2025
Debt Instrument [Line Items]
Stated interest rate	4.75%
Senior Notes | 3.700% notes due 2027
Debt Instrument [Line Items]
Stated interest rate	3.70%
Senior Notes | 4.450% notes due 2028
Debt Instrument [Line Items]
Stated interest rate	4.45%
Senior Notes | 4.750% notes due 2023
Debt Instrument [Line Items]
Stated interest rate	4.75%
Senior Notes | 2.750% notes due 2024
Debt Instrument [Line Items]
Stated interest rate	2.75%
Senior Notes | 4.250% notes due 2025
Debt Instrument [Line Items]
Stated interest rate	4.25%
Senior Notes | 3.300% notes due 2029
Debt Instrument [Line Items]
Stated interest rate	3.30%
Senior Notes | 2.625% notes due 2024
Debt Instrument [Line Items]
Stated interest rate	2.625%

Debt of the Operating Partner_3

Debt of the Operating Partnership (Summary of Outstanding Indebtedness) (Details) $ in Thousands	Jan. 15, 2016extension	Sep. 30, 2018USD ($)$ / €$ / £	Dec. 31, 2017USD ($)$ / €$ / £
3.950% notes due 2022
Debt Instrument [Line Items]
Stated interest rate		3.95%
3.625% notes due 2022
Debt Instrument [Line Items]
Stated interest rate		3.625%
2.625% notes due 2024
Debt Instrument [Line Items]
Stated interest rate		2.625%
2.750% notes due 2024
Debt Instrument [Line Items]
Stated interest rate		2.75%
4.750% notes due 2025
Debt Instrument [Line Items]
Stated interest rate		4.75%
Global revolving credit facility
Debt Instrument [Line Items]
Deferred financing costs		$ (4,700)	$ (7,200)
Unsecured Term Loans
Debt Instrument [Line Items]
Deferred financing costs		(3,700)	(4,800)
Unsecured Senior Notes
Debt Instrument [Line Items]
Deferred financing costs		$ (38,300)	(37,800)
Unsecured Senior Notes | 5.875% notes due 2020
Debt Instrument [Line Items]
Stated interest rate		5.875%
Unsecured Senior Notes | 5.250% notes due 2021
Debt Instrument [Line Items]
Stated interest rate		5.25%
Unsecured Senior Notes | 3.950% notes due 2022
Debt Instrument [Line Items]
Stated interest rate		3.95%
Unsecured Senior Notes | 3.625% notes due 2022
Debt Instrument [Line Items]
Stated interest rate		3.625%
Unsecured Senior Notes | 2.750% notes due 2023
Debt Instrument [Line Items]
Stated interest rate		2.75%
Unsecured Senior Notes | 4.750% notes due 2023
Debt Instrument [Line Items]
Stated interest rate		4.75%
Unsecured Senior Notes | 2.625% notes due 2024
Debt Instrument [Line Items]
Stated interest rate		2.625%
Unsecured Senior Notes | 2.750% notes due 2024
Debt Instrument [Line Items]
Stated interest rate		2.75%
Unsecured Senior Notes | 4.250% notes due 2025
Debt Instrument [Line Items]
Stated interest rate		4.25%
Unsecured Senior Notes | 4.750% notes due 2025
Debt Instrument [Line Items]
Stated interest rate		4.75%
Unsecured Senior Notes | 3.700% notes due 2027
Debt Instrument [Line Items]
Stated interest rate		3.70%
Unsecured Senior Notes | 4.450% notes due 2028
Debt Instrument [Line Items]
Stated interest rate		4.45%
Unsecured Senior Notes | 3.300% notes due 2029
Debt Instrument [Line Items]
Stated interest rate		3.30%
Mortgage Loans
Debt Instrument [Line Items]
Deferred financing costs		$ 0	0
Digital Realty Trust, L.P.
Debt Instrument [Line Items]
Long-term debt, gross		9,242,935
Total indebtedness		9,179,871	8,648,618
Unamortized discounts		(16,495)
Unamortized net premiums		171
Long-term debt, net of discount (premium)		$ 9,226,611
Digital Realty Trust, L.P. | Unsecured term loan — 5-year
Debt Instrument [Line Items]
Interest rate basis spread		1.10%
Debt instrument term	5 years
Digital Realty Trust, L.P. | Unsecured term loan — 7-year
Debt Instrument [Line Items]
Interest rate basis spread		1.55%
Debt instrument term	7 years
Digital Realty Trust, L.P. | Global revolving credit facility
Debt Instrument [Line Items]
Long-term debt, gross		$ 594,983	558,191
Deferred financing costs		(4,694)	(7,245)
Total indebtedness		590,289	$ 550,946
Unamortized discounts		0
Unamortized net premiums		0
Long-term debt, net of discount (premium)		$ 594,983
Commitment fee percentage		0.20%
Number of extension options | extension	2
Debt instrument, extension term	6 months
Interest rate basis spread		1.00%
Digital Realty Trust, L.P. | Global revolving credit facility | British pound sterling (£)
Debt Instrument [Line Items]
Exchange rate | $ / £			1.35
Digital Realty Trust, L.P. | Global revolving credit facility | Euro (€)
Debt Instrument [Line Items]
Exchange rate | $ / €		1.16	1.20
Digital Realty Trust, L.P. | Unsecured Term Loans
Debt Instrument [Line Items]
Long-term debt, gross		$ 1,356,702	$ 1,425,117
Deferred financing costs		(3,733)	(4,784)
Total indebtedness		1,352,969	1,420,333
Unamortized discounts		0
Unamortized net premiums		0
Long-term debt, net of discount (premium)		1,356,702
Digital Realty Trust, L.P. | Unsecured Term Loans | British pound sterling (£)
Debt Instrument [Line Items]
Long-term debt, gross		$ 220,843	$ 229,011
Exchange rate | $ / £		1.30	1.35
Digital Realty Trust, L.P. | Unsecured Term Loans | Euro (€)
Debt Instrument [Line Items]
Exchange rate | $ / €		1.16	1.20
Digital Realty Trust, L.P. | Unsecured Term Loans | Unsecured term loan — 5-year
Debt Instrument [Line Items]
Long-term debt, gross		$ 1,056,702	$ 1,125,117
Interest rate basis spread		1.10%
Debt instrument term		5 years
Digital Realty Trust, L.P. | Unsecured Term Loans | Unsecured term loan — 7-year
Debt Instrument [Line Items]
Long-term debt, gross		$ 300,000	300,000
Interest rate basis spread		1.55%
Debt instrument term		7 years
Digital Realty Trust, L.P. | Unsecured Senior Notes
Debt Instrument [Line Items]
Long-term debt, gross		$ 7,185,320
Deferred financing costs		(38,284)	(37,788)
Total indebtedness		7,130,541	6,570,757
Unamortized discounts		(16,495)	(18,508)
Unamortized net premiums		0
Long-term debt, net of discount (premium)		7,168,825	6,608,545
Digital Realty Trust, L.P. | Unsecured Senior Notes | Floating rate notes due 2019
Debt Instrument [Line Items]
Long-term debt, gross		$ 145,050	150,063
Digital Realty Trust, L.P. | Unsecured Senior Notes | Floating rate notes due 2019 | EURIBOR
Debt Instrument [Line Items]
Interest rate basis spread		0.50%
Digital Realty Trust, L.P. | Unsecured Senior Notes | 5.875% notes due 2020
Debt Instrument [Line Items]
Long-term debt, gross		$ 500,000	500,000
Stated interest rate		5.875%
Digital Realty Trust, L.P. | Unsecured Senior Notes | 3.400% notes due 2020
Debt Instrument [Line Items]
Long-term debt, gross		$ 500,000	500,000
Stated interest rate		3.40%
Digital Realty Trust, L.P. | Unsecured Senior Notes | 5.250% notes due 2021
Debt Instrument [Line Items]
Long-term debt, gross		$ 400,000	400,000
Stated interest rate		5.25%
Digital Realty Trust, L.P. | Unsecured Senior Notes | 3.950% notes due 2022
Debt Instrument [Line Items]
Long-term debt, gross		$ 500,000	500,000
Stated interest rate		3.95%
Digital Realty Trust, L.P. | Unsecured Senior Notes | 3.625% notes due 2022
Debt Instrument [Line Items]
Long-term debt, gross		$ 300,000	300,000
Stated interest rate		3.625%
Digital Realty Trust, L.P. | Unsecured Senior Notes | 2.750% notes due 2023
Debt Instrument [Line Items]
Long-term debt, gross		$ 350,000	350,000
Stated interest rate		2.75%
Digital Realty Trust, L.P. | Unsecured Senior Notes | 4.750% notes due 2023
Debt Instrument [Line Items]
Long-term debt, gross		$ 390,930	405,390
Stated interest rate		4.75%
Digital Realty Trust, L.P. | Unsecured Senior Notes | 2.625% notes due 2024
Debt Instrument [Line Items]
Long-term debt, gross		$ 696,240	720,300
Stated interest rate		2.625%
Digital Realty Trust, L.P. | Unsecured Senior Notes | 2.750% notes due 2024
Debt Instrument [Line Items]
Long-term debt, gross		$ 325,775	337,825
Stated interest rate		2.75%
Digital Realty Trust, L.P. | Unsecured Senior Notes | 4.250% notes due 2025
Debt Instrument [Line Items]
Long-term debt, gross		$ 521,240	540,520
Stated interest rate		4.25%
Digital Realty Trust, L.P. | Unsecured Senior Notes | 4.750% notes due 2025
Debt Instrument [Line Items]
Long-term debt, gross		$ 450,000	450,000
Stated interest rate		4.75%
Digital Realty Trust, L.P. | Unsecured Senior Notes | 3.700% notes due 2027
Debt Instrument [Line Items]
Long-term debt, gross		$ 1,000,000	1,000,000
Stated interest rate		3.70%
Digital Realty Trust, L.P. | Unsecured Senior Notes | 4.450% notes due 2028
Debt Instrument [Line Items]
Long-term debt, gross		$ 650,000	0
Stated interest rate		4.45%
Digital Realty Trust, L.P. | Unsecured Senior Notes | 3.300% notes due 2029
Debt Instrument [Line Items]
Long-term debt, gross		$ 456,085	472,955
Stated interest rate		3.30%
Digital Realty Trust, L.P. | Unsecured Senior Notes | Secured note due 2023 | LIBOR
Debt Instrument [Line Items]
Interest rate basis spread		1.10%
Digital Realty Trust, L.P. | Mortgage Loans
Debt Instrument [Line Items]
Long-term debt, gross		$ 105,930
Deferred financing costs		(29)	(29)
Total indebtedness		106,072	106,582
Unamortized discounts		0
Unamortized net premiums		171	241
Long-term debt, net of discount (premium)		106,101	106,611
Digital Realty Trust, L.P. | Mortgage Loans | 731 East Trade Street
Debt Instrument [Line Items]
Long-term debt, gross		$ 1,930	2,370
Effective interest rate (as a percent)		8.22%
Digital Realty Trust, L.P. | Mortgage Loans | Secured note due 2023
Debt Instrument [Line Items]
Long-term debt, gross		$ 104,000	$ 104,000

Debt of the Operating Partner_4

Debt of the Operating Partnership (Floating and Base Rate Borrowing) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2018USD ($)$ / $$ / €$ / ¥$ / $$ / $$ / $	Dec. 31, 2017USD ($)$ / €$ / ¥$ / £$ / $$ / $
Base Rate
Debt Instrument [Line Items]
Interest rate basis spread	0.00%
Digital Realty Trust, L.P.
Debt Instrument [Line Items]
Long-term debt, gross	$ 9,242,935
Digital Realty Trust, L.P. | Global revolving credit facility
Debt Instrument [Line Items]
Long-term debt, gross	$ 594,983	$ 558,191
Weighted-average interest rate	2.35%	2.21%
Interest rate basis spread	1.00%
Digital Realty Trust, L.P. | Global revolving credit facility | Floating Rate
Debt Instrument [Line Items]
Long-term debt, gross	$ 589,983	$ 543,191
Weighted-average interest rate	2.32%	2.15%
Interest rate basis spread	1.00%
Digital Realty Trust, L.P. | U.S. dollar ($) | Global revolving credit facility | Floating Rate
Debt Instrument [Line Items]
Long-term debt, gross	$ 240,000	$ 400,000
Weighted-average interest rate	3.23%	2.48%
Digital Realty Trust, L.P. | U.S. dollar ($) | Global revolving credit facility | Base Rate
Debt Instrument [Line Items]
Long-term debt, gross	$ 5,000	$ 15,000
Weighted-average interest rate	5.25%	4.50%
Digital Realty Trust, L.P. | British pound sterling (£) | Global revolving credit facility
Debt Instrument [Line Items]
Exchange rate | $ / £		1.35
Digital Realty Trust, L.P. | British pound sterling (£) | Global revolving credit facility | Floating Rate
Debt Instrument [Line Items]
Long-term debt, gross	$ 0	$ 18,918
Weighted-average interest rate	0.00%	1.50%
Digital Realty Trust, L.P. | Euro (€) | Global revolving credit facility
Debt Instrument [Line Items]
Exchange rate | $ / €	1.16	1.20
Digital Realty Trust, L.P. | Euro (€) | Global revolving credit facility | Floating Rate
Debt Instrument [Line Items]
Long-term debt, gross	$ 74,846	$ 31,213
Weighted-average interest rate	0.62%	0.62%
Digital Realty Trust, L.P. | Australian dollar (AUD) | Global revolving credit facility
Debt Instrument [Line Items]
Exchange rate | $ / $	0.72
Digital Realty Trust, L.P. | Australian dollar (AUD) | Global revolving credit facility | Floating Rate
Debt Instrument [Line Items]
Long-term debt, gross	$ 58,659	$ 0
Weighted-average interest rate	2.85%	0.00%
Digital Realty Trust, L.P. | Hong Kong dollar (HKD) | Global revolving credit facility
Debt Instrument [Line Items]
Exchange rate | $ / $	0.13	0.13
Digital Realty Trust, L.P. | Hong Kong dollar (HKD) | Global revolving credit facility | Floating Rate
Debt Instrument [Line Items]
Long-term debt, gross	$ 7,779	$ 4,100
Weighted-average interest rate	2.91%	2.20%
Digital Realty Trust, L.P. | Japanese yen (JPY) | Global revolving credit facility
Debt Instrument [Line Items]
Exchange rate | $ / ¥	0.01	0.01
Digital Realty Trust, L.P. | Japanese yen (JPY) | Global revolving credit facility | Floating Rate
Debt Instrument [Line Items]
Long-term debt, gross	$ 116,195	$ 65,890
Weighted-average interest rate	0.90%	0.96%
Digital Realty Trust, L.P. | Singapore dollar (SGD) | Global revolving credit facility
Debt Instrument [Line Items]
Exchange rate | $ / $	0.73
Digital Realty Trust, L.P. | Singapore dollar (SGD) | Global revolving credit facility | Floating Rate
Debt Instrument [Line Items]
Long-term debt, gross	$ 25,114	$ 0
Weighted-average interest rate	2.61%	0.00%
Digital Realty Trust, L.P. | Canadian dollar (CAD) | Global revolving credit facility
Debt Instrument [Line Items]
Exchange rate | $ / $	0.77	0.80
Digital Realty Trust, L.P. | Canadian dollar (CAD) | Global revolving credit facility | Floating Rate
Debt Instrument [Line Items]
Long-term debt, gross	$ 67,390	$ 23,070
Weighted-average interest rate	2.82%	2.36%

Debt of the Operating Partner_5

Debt of the Operating Partnership (Weighted-average Interest Rate by Denomination of Draw) (Details) - Digital Realty Trust, L.P. $ in Thousands	Sep. 30, 2018USD ($)$ / $$ / ¥$ / £$ / $$ / $$ / $	Dec. 31, 2017USD ($)$ / $$ / ¥$ / £$ / $$ / $$ / $
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

Debt of the Operating Partner_6

Debt of the Operating Partnership (Global Revolving Credit Facility) (Narrative) (Details) - Global revolving credit facility, net	Jan. 15, 2016USD ($)extension	Sep. 30, 2018USD ($)	Aug. 15, 2013USD ($)
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity	$ 2,000,000,000
Digital Realty Trust, L.P.
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity	$ 2,000,000,000		$ 2,000,000,000
Number of extension options | extension	2
Revolving credit facility commitments extension	6 months
Interest rate basis spread		1.00%
Commitment fee percentage		0.20%
Letter of credit security amount		$ 44,600,000
Digital Realty Trust, L.P. | Accordian Feature
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity	$ 2,500,000,000

Debt of the Operating Partner_7

Debt of the Operating Partnership (Unsecured Term Loan) (Narrative) (Details) - USD ($)	Jan. 15, 2016	Sep. 30, 2018	Dec. 31, 2017	Apr. 16, 2012
Unsecured Term Loans
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity	$ 1.55
Digital Realty Trust, L.P.
Debt Instrument [Line Items]
Long-term debt, gross		$ 9,242,935,000
Digital Realty Trust, L.P. | Unsecured Term Loans
Debt Instrument [Line Items]
Long-term debt, gross		$ 1,356,702,000	$ 1,425,117,000
Digital Realty Trust, L.P. | Unsecured term loan — 5-year
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity	$ 1,250,000,000
Debt instrument term	5 years
Interest rate basis spread		1.10%
Digital Realty Trust, L.P. | Unsecured term loan — 5-year | Unsecured Term Loans
Debt Instrument [Line Items]
Debt instrument term		5 years
Interest rate basis spread		1.10%
Long-term debt, gross		$ 1,056,702,000	1,125,117,000
Digital Realty Trust, L.P. | Unsecured term loan — 7-year
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity	$ 300,000,000
Debt instrument term	7 years
Interest rate basis spread		1.55%
Digital Realty Trust, L.P. | Unsecured term loan — 7-year | Unsecured Term Loans
Debt Instrument [Line Items]
Debt instrument term		7 years
Interest rate basis spread		1.55%
Long-term debt, gross		$ 300,000,000	$ 300,000,000
Digital Realty Trust, L.P. | Unsecured Term Loans
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity		1,550,000,000		$ 1,000,000,000
Credit facility, maximum borrowing capacity, subject to receipt of lender commitments and other conditions		$ 1,800,000,000

Debt of Operating Partnership (

Debt of Operating Partnership (3.750% Notes due 2030) (Details) - Subsequent Event Type - 3.750% Notes due 2030 - Digital Realty Trust, L.P. $ in Millions	Oct. 17, 2018USD ($)	Oct. 17, 2018GBP (£)	Oct. 17, 2018GBP (£)
Debt Instrument [Line Items]
Debt face amount	$ 524.6		£ 400,000,000
Net proceeds from offering	$ 516.1	£ 393,500,000
Covenant, leverage ratio percentage, required maximum	60.00%	60.00%
Covenant, secured leverage ratio, allowable maximum	40.00%	40.00%
Covenant, interest coverage ratio, required minimum	1.50	1.50
Covenant, unencumbered assets to unsecured debt	150.00%	150.00%
Senior Notes
Debt Instrument [Line Items]
Stated interest rate	3.75%		3.75%

Debt of the Operating Partner_8

Debt of the Operating Partnership (Schedule of Debt Maturities And Principal Maturities) (Details) - Digital Realty Trust, L.P. $ in Thousands	Jan. 15, 2016extension	Sep. 30, 2018USD ($)	Dec. 31, 2017USD ($)
Debt Instrument [Line Items]
Remainder of 2018		$ 153
2,019		145,694
2,020		1,596,116
2,021		1,456,702
2,022		800,000
Thereafter		5,244,270
Subtotal		9,242,935
Unamortized discounts		(16,495)
Unamortized premium		171
Long-term debt, net of discount (premium)		9,226,611
Global revolving credit facility, net
Debt Instrument [Line Items]
Remainder of 2018		0
2,019		0
2,020		594,983
2,021		0
2,022		0
Thereafter		0
Subtotal		594,983	$ 558,191
Unamortized discounts		0
Unamortized premium		0
Long-term debt, net of discount (premium)		594,983
Number of extension options | extension	2
Revolving credit facility commitments extension	6 months
Unsecured Term Loans
Debt Instrument [Line Items]
Remainder of 2018		0
2,019		0
2,020		0
2,021		1,056,702
2,022		0
Thereafter		300,000
Subtotal		1,356,702	1,425,117
Unamortized discounts		0
Unamortized premium		0
Long-term debt, net of discount (premium)		1,356,702
Unsecured Senior Notes
Debt Instrument [Line Items]
Remainder of 2018		0
2,019		145,050
2,020		1,000,000
2,021		400,000
2,022		800,000
Thereafter		4,840,270
Subtotal		7,185,320
Unamortized discounts		(16,495)	(18,508)
Unamortized premium		0
Long-term debt, net of discount (premium)		7,168,825	6,608,545
Mortgage Loans
Debt Instrument [Line Items]
Remainder of 2018		153
2,019		644
2,020		1,133
2,021		0
2,022		0
Thereafter		104,000
Subtotal		105,930
Unamortized discounts		0
Unamortized premium		171	241
Long-term debt, net of discount (premium)		$ 106,101	$ 106,611

Income per Share (Summary of Ba

Income per Share (Summary of Basic and Diluted Earnings per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share [Abstract]
Net income (loss) available to common stockholders	$ 67,268	$ (4,140)	$ 218,700	$ 119,842
Weighted average shares outstanding-basic (in shares)	206,118,472	170,194,254	205,931,031	163,481,306
Potentially dilutive common shares:
Unvested incentive units (shares)	169,100	0	160,117	150,369
Forward equity offering (shares)	37,884	0	1,847	166,493
Market performance-based awards (shares)	440,800	0	462,632	572,928
Weighted average shares/units outstanding-diluted (shares/units)	206,766,256	170,194,254	206,555,627	164,371,096
Income (loss) per share:
Basic (in dollars per share)	$ 0.33	$ (0.02)	$ 1.06	$ 0.73
Diluted (in dollars per share)	$ 0.33	$ (0.02)	$ 1.06	$ 0.73

Income per Share (Schedule of A

Income per Share (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 (shares)	19,036,184	12,245,217	19,993,742	11,487,387
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 (shares)	8,170,912	3,266,451	8,268,382	2,566,766
Potentially dilutive Series C Cumulative Redeemable Perpetual Preferred Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (shares)	1,727,724	329,709	1,864,489	109,903
Potentially dilutive Series F Cumulative Redeemable Preferred Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (shares)	0	0	0	617,734
Potentially dilutive Series G Cumulative Redeemable Preferred Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (shares)	2,142,282	2,193,331	2,311,864	2,262,875
Potentially dilutive Series H Cumulative Redeemable Preferred Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (shares)	3,139,291	3,214,098	3,387,795	3,316,008
Potentially dilutive Series I Cumulative Redeemable Preferred Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (shares)	2,144,789	2,195,898	2,314,569	2,265,524
Potentially dilutive Series J Cumulative Redeemable Preferred Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (shares)	1,711,186	1,045,730	1,846,643	348,577

Income per Unit (Summary of Bas

Income per Unit (Summary of Basic and Diluted Earnings per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Class of Stock [Line Items]
Net income (loss) available to common unitholders	$ 67,268	$ (4,140)	$ 218,700	$ 119,842
Weighted average units outstanding-basic (in units)	206,118,472	170,194,254	205,931,031	163,481,306
Potentially dilutive common units:
Unvested incentive units (units)	169,100	0	160,117	150,369
Forward equity offering (units)	37,884	0	1,847	166,493
Market performance-based awards (units)	440,800	0	462,632	572,928
Weighted average shares/units outstanding-diluted (shares/units)	206,766,256	170,194,254	206,555,627	164,371,096
Income (loss) per share:
Basic (in dollars per unit)	$ 0.33	$ (0.02)	$ 1.06	$ 0.73
Diluted (in dollars per unit)	$ 0.33	$ (0.02)	$ 1.06	$ 0.73
Digital Realty Trust, L.P.
Class of Stock [Line Items]
Net income (loss) available to common unitholders	$ 69,968	$ (4,219)	$ 227,580	$ 121,474
Weighted average units outstanding-basic (in units)	214,289,384	173,460,704	214,199,414	166,048,072
Potentially dilutive common units:
Unvested incentive units (units)	169,100	0	160,117	166,493
Forward equity offering (units)	37,884	0	1,847	150,369
Market performance-based awards (units)	440,800	0	462,632	572,928
Weighted average shares/units outstanding-diluted (shares/units)	214,937,168	173,460,704	214,824,010	166,937,862
Income (loss) per share:
Basic (in dollars per unit)	$ 0.33	$ (0.02)	$ 1.06	$ 0.73
Diluted (in dollars per unit)	$ 0.33	$ (0.02)	$ 1.06	$ 0.73

Income per Unit (Schedule of An

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

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Percentage of income distributed (at least)	100.00%
Net deferred tax liability	$ 158.3	$ 167

Equity and Accumulated Other _3

Equity and Accumulated Other Comprehensive Loss, Net Equity and Accumulated Other Comprehensive Loss, Net (Forward Equity Sale) (Details) - Digital Realty Trust, L.P. - USD ($) $ in Billions	Sep. 27, 2019	Sep. 27, 2018
Forward Sale Agreement
Class of Stock [Line Items]
Common stock issued in public offering (in shares)		9,775,000
Over-Allotment Option
Class of Stock [Line Items]
Common stock issued in public offering (in shares)		1,275,000
Scenario, Forecast | Forward Sale Agreement
Class of Stock [Line Items]
Net proceeds on public offering	$ 1.1

Equity and Accumulated Other _4

Equity and Accumulated Other Comprehensive Loss, Net (Noncontrolling Interests in Operating Partnership) (Details) $ in Millions	Sep. 30, 2018USD ($)shares	Dec. 31, 2017USD ($)shares
Class of Stock [Line Items]
Number of units (units)	206,267,055	205,470,300
Percentage of total	96.10%	96.00%
Common stock conversion ratio	1
Common units held by third parties
Class of Stock [Line Items]
Common units held by third parties (units)	6,411,484	6,899,094
Percentage of total	3.00%	3.20%
Incentive units held by employees and directors (see Note 14)
Class of Stock [Line Items]
Incentive units held by employees and directors (units)	1,929,103	1,590,001
Percentage of total	0.90%	0.80%
Noncontrolling Interests in Operating Partnership
Class of Stock [Line Items]
Number of units (units)	214,607,642	213,959,395
Percentage of total	100.00%	100.00%
Digital Realty Trust, L.P.
Class of Stock [Line Items]
Common stock conversion ratio	1
Redeemable noncontrolling interests – operating partnership | $	$ 891	$ 887

Equity and Accumulated Other _5

Equity and Accumulated Other Comprehensive Loss, Net (Summary of Activity For Noncontrolling Interests in The Operating Partnership) (Details)	9 Months Ended
	Sep. 30, 2018shares
Common and Incentive Unit Activity [Roll Forward]
As of December 31, 2017 (units)	8,489,095
Redemption of common units for shares of Digital Realty Trust, Inc. common stock (units)	(487,610)
Conversion of incentive units held by employees and directors for shares of Digital Realty Trust, Inc. common stock	(80,182)
Incentive units issued upon achievement of market performance condition	326,947
Grant of incentive units to employees and directors	114,472
Cancellation / forfeitures of incentive units held by employees and directors	(22,135)
As of June 30, 2018 (units)	8,340,587
Common Units
Common and Incentive Unit Activity [Roll Forward]
As of December 31, 2017 (units)	6,899,094
Redemption of common units for shares of Digital Realty Trust, Inc. common stock (units)	(487,610)
Conversion of incentive units held by employees and directors for shares of Digital Realty Trust, Inc. common stock	0
Incentive units issued upon achievement of market performance condition	0
Grant of incentive units to employees and directors	0
Cancellation / forfeitures of incentive units held by employees and directors	0
As of June 30, 2018 (units)	6,411,484
Incentive Units
Common and Incentive Unit Activity [Roll Forward]
As of December 31, 2017 (units)	1,590,001
Redemption of common units for shares of Digital Realty Trust, Inc. common stock (units)	0
Conversion of incentive units held by employees and directors for shares of Digital Realty Trust, Inc. common stock	(80,182)
Incentive units issued upon achievement of market performance condition	326,947
Grant of incentive units to employees and directors	114,472
Cancellation / forfeitures of incentive units held by employees and directors	(22,135)
As of June 30, 2018 (units)	1,929,103

Equity and Accumulated Other _6

Equity and Accumulated Other Comprehensive Loss, Net (Schedule of Dividends) (Details) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2018USD ($)$ / shares
Series C Preferred Stock
Dividends Payable [Line Items]
Dividends, preferred stock	$ 9,999
Preferred stock dividend per share amount (in dollars per share) | $ / shares	$ 1.65625
Series C Preferred Stock | March 1, 2018 Installment
Dividends Payable [Line Items]
Dividends, preferred stock	$ 3,333
Series C Preferred Stock | May 8, 2018 Installment
Dividends Payable [Line Items]
Dividends, preferred stock	3,333
Series C Preferred Stock | August 11, 2018 Installment
Dividends Payable [Line Items]
Dividends, preferred stock	3,333
Series G Preferred Stock
Dividends Payable [Line Items]
Dividends, preferred stock	$ 11,016
Preferred stock dividend per share amount (in dollars per share) | $ / shares	$ 1.46875
Series G Preferred Stock | March 1, 2018 Installment
Dividends Payable [Line Items]
Dividends, preferred stock	$ 3,672
Series G Preferred Stock | May 8, 2018 Installment
Dividends Payable [Line Items]
Dividends, preferred stock	3,672
Series G Preferred Stock | August 11, 2018 Installment
Dividends Payable [Line Items]
Dividends, preferred stock	3,672
Series H Preferred Stock
Dividends Payable [Line Items]
Dividends, preferred stock	$ 20,190
Preferred stock dividend per share amount (in dollars per share) | $ / shares	$ 1.84375
Series H Preferred Stock | March 1, 2018 Installment
Dividends Payable [Line Items]
Dividends, preferred stock	$ 6,730
Series H Preferred Stock | May 8, 2018 Installment
Dividends Payable [Line Items]
Dividends, preferred stock	6,730
Series H Preferred Stock | August 11, 2018 Installment
Dividends Payable [Line Items]
Dividends, preferred stock	6,730
Series I Preferred Stock
Dividends Payable [Line Items]
Dividends, preferred stock	$ 11,907
Preferred stock dividend per share amount (in dollars per share) | $ / shares	$ 1.5875
Series I Preferred Stock | March 1, 2018 Installment
Dividends Payable [Line Items]
Dividends, preferred stock	$ 3,969
Series I Preferred Stock | May 8, 2018 Installment
Dividends Payable [Line Items]
Dividends, preferred stock	3,969
Series I Preferred Stock | August 11, 2018 Installment
Dividends Payable [Line Items]
Dividends, preferred stock	3,969
Series J Preferred Stock
Dividends Payable [Line Items]
Dividends, preferred stock	$ 7,875
Preferred stock dividend per share amount (in dollars per share) | $ / shares	$ 1.3125
Series J Preferred Stock | March 1, 2018 Installment
Dividends Payable [Line Items]
Dividends, preferred stock	$ 2,625
Series J Preferred Stock | May 8, 2018 Installment
Dividends Payable [Line Items]
Dividends, preferred stock	2,625
Series J Preferred Stock | August 11, 2018 Installment
Dividends Payable [Line Items]
Dividends, preferred stock	2,625
Common Stock
Dividends Payable [Line Items]
Dividends, common stock	$ 624,252
Common stock dividend per share amount (in dollars per share) | $ / shares	$ 4.04
Common Stock | March 1, 2018 Installment
Dividends Payable [Line Items]
Dividends, common stock	$ 208,015
Common Stock | May 8, 2018 Installment
Dividends Payable [Line Items]
Dividends, common stock	208,071
Common Stock | August 11, 2018 Installment
Dividends Payable [Line Items]
Dividends, common stock	$ 208,166

Equity and Accumulated Other _7

Equity and Accumulated Other Comprehensive Loss, Net (Schedule of Accumulated Other Comprehensive Loss, Net) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2018USD ($)
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	$ 11,049,450
Net current period change	7,433
Reclassification to interest expense from interest rate swaps	(2,202)
Ending balance	10,763,462
Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(147,370)
Net current period change	(8,272)
Reclassification to interest expense from interest rate swaps	0
Ending balance	(155,642)
Cash flow hedge adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	13,200
Net current period change	15,705
Reclassification to interest expense from interest rate swaps	(2,202)
Ending balance	26,703
Foreign currency net investment hedge adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	25,738
Net current period change	0
Reclassification to interest expense from interest rate swaps	0
Ending balance	25,738
Accumulated other comprehensive income (loss), net
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(108,432)
Ending balance	$ (103,201)

Capital and Accumulated Other_3

Capital and Accumulated Other Comprehensive Loss Capital and Accumulated Other Comprehensive Loss (Forward Equity Sale) (Details) - Digital Realty Trust, L.P. - USD ($) $ in Billions	Sep. 27, 2019	Sep. 27, 2018
Forward Sale Agreement
Class of Stock [Line Items]
Common stock issued in public offering (in shares)		9,775,000
Over-Allotment Option
Class of Stock [Line Items]
Common stock issued in public offering (in shares)		1,275,000
Scenario, Forecast | Forward Sale Agreement
Class of Stock [Line Items]
Net proceeds on public offering	$ 1.1

Capital and Accumulated Other_4

Capital and Accumulated Other Comprehensive Loss (Partnership Units Narrative) (Details) $ in Millions	Sep. 30, 2018USD ($)	Dec. 31, 2017USD ($)
Class of Stock [Line Items]
Common stock conversion ratio	1
Digital Realty Trust, L.P.
Class of Stock [Line Items]
Common stock conversion ratio	1
Redeemable noncontrolling interests – operating partnership	$ 891	$ 887

Capital and Accumulated Other_5

Capital and Accumulated Other Comprehensive Loss (Schedule of Distributions) (Details) - Digital Realty Trust, L.P. $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2018USD ($)$ / shares
Series C Preferred Units
Dividends Payable [Line Items]
Dividends/Distributions, preferred units	$ 9,999
Preferred stock dividend per share amount (in dollars per share/unit) | $ / shares	$ 1.65625
Potentially dilutive Series G Cumulative Redeemable Preferred Units
Dividends Payable [Line Items]
Dividends/Distributions, preferred units	$ 11,016
Preferred stock dividend per share amount (in dollars per share/unit) | $ / shares	$ 1.46875
Potentially dilutive Series H Cumulative Redeemable Preferred Units
Dividends Payable [Line Items]
Dividends/Distributions, preferred units	$ 20,190
Preferred stock dividend per share amount (in dollars per share/unit) | $ / shares	$ 1.84375
Series I Preferred Units
Dividends Payable [Line Items]
Dividends/Distributions, preferred units	$ 11,907
Preferred stock dividend per share amount (in dollars per share/unit) | $ / shares	$ 1.5875
Series J Preferred Units
Dividends Payable [Line Items]
Dividends/Distributions, preferred units	$ 7,875
Preferred stock dividend per share amount (in dollars per share/unit) | $ / shares	$ 1.3125
Common Units
Dividends Payable [Line Items]
Dividends/Distributions, common stock/units	$ 650,567
Common stock dividend per share amount (in dollars per share/unit) | $ / shares	$ 4.04
March 1, 2018 Installment | Series C Preferred Units
Dividends Payable [Line Items]
Dividends/Distributions, preferred units	$ 3,333
March 1, 2018 Installment | Potentially dilutive Series G Cumulative Redeemable Preferred Units
Dividends Payable [Line Items]
Dividends/Distributions, preferred units	3,672
March 1, 2018 Installment | Potentially dilutive Series H Cumulative Redeemable Preferred Units
Dividends Payable [Line Items]
Dividends/Distributions, preferred units	6,730
March 1, 2018 Installment | Series I Preferred Units
Dividends Payable [Line Items]
Dividends/Distributions, preferred units	3,969
March 1, 2018 Installment | Series J Preferred Units
Dividends Payable [Line Items]
Dividends/Distributions, preferred units	2,625
March 1, 2018 Installment | Common Units
Dividends Payable [Line Items]
Dividends/Distributions, common stock/units	216,953
May 8, 2018 Installment | Series C Preferred Units
Dividends Payable [Line Items]
Dividends/Distributions, preferred units	3,333
May 8, 2018 Installment | Potentially dilutive Series G Cumulative Redeemable Preferred Units
Dividends Payable [Line Items]
Dividends/Distributions, preferred units	3,672
May 8, 2018 Installment | Potentially dilutive Series H Cumulative Redeemable Preferred Units
Dividends Payable [Line Items]
Dividends/Distributions, preferred units	6,730
May 8, 2018 Installment | Series I Preferred Units
Dividends Payable [Line Items]
Dividends/Distributions, preferred units	3,969
May 8, 2018 Installment | Series J Preferred Units
Dividends Payable [Line Items]
Dividends/Distributions, preferred units	2,625
May 8, 2018 Installment | Common Units
Dividends Payable [Line Items]
Dividends/Distributions, common stock/units	216,789
August 11, 2018 Installment | Series C Preferred Units
Dividends Payable [Line Items]
Dividends/Distributions, preferred units	3,333
August 11, 2018 Installment | Potentially dilutive Series G Cumulative Redeemable Preferred Units
Dividends Payable [Line Items]
Dividends/Distributions, preferred units	3,672
August 11, 2018 Installment | Potentially dilutive Series H Cumulative Redeemable Preferred Units
Dividends Payable [Line Items]
Dividends/Distributions, preferred units	6,730
August 11, 2018 Installment | Series I Preferred Units
Dividends Payable [Line Items]
Dividends/Distributions, preferred units	3,969
August 11, 2018 Installment | Series J Preferred Units
Dividends Payable [Line Items]
Dividends/Distributions, preferred units	2,625
August 11, 2018 Installment | Common Units
Dividends Payable [Line Items]
Dividends/Distributions, common stock/units	$ 216,825

Capital and Accumulated Other_6

Capital and Accumulated Other Comprehensive Loss (Schedule of Accumulated Other Comprehensive Loss) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2018USD ($)
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Net current period change	$ 7,433
Reclassification to interest expense from interest rate swaps	(2,202)
Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Net current period change	(8,272)
Reclassification to interest expense from interest rate swaps	0
Cash flow hedge adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Net current period change	15,705
Reclassification to interest expense from interest rate swaps	(2,202)
Foreign currency net investment hedge adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Net current period change	0
Reclassification to interest expense from interest rate swaps	0
Digital Realty Trust, L.P.
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	11,049,450
Net current period change	7,728
Reclassification to interest expense from interest rate swaps	(2,289)
Ending Balance	10,763,462
Digital Realty Trust, L.P. | Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(151,795)
Net current period change	(8,608)
Reclassification to interest expense from interest rate swaps	0
Ending Balance	(160,403)
Digital Realty Trust, L.P. | Cash flow hedge adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	12,758
Net current period change	16,336
Reclassification to interest expense from interest rate swaps	(2,289)
Ending Balance	26,805
Digital Realty Trust, L.P. | Foreign currency net investment hedge adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	26,152
Net current period change	0
Reclassification to interest expense from interest rate swaps	0
Ending Balance	26,152
Digital Realty Trust, L.P. | Accumulated other comprehensive income (loss), net
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(112,885)
Ending Balance	$ (107,446)

Incentive Plan (Narrative) (Det

Incentive Plan (Narrative) (Details) shares in Millions	Sep. 22, 2017shares	Sep. 30, 2018shares
2004 Incentive Award Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional shares registered for issuance, 2014 Incentive Award Plan	3.7
2014 Incentive Award Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares remaining for issuance under the Incentive Plan (shares)		7.1
Conversion of units to shares ratio		1

Incentive Plan Incentive Plan (

Incentive Plan Incentive Plan (Schedule of Deferred and Unearned Compensation) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Long-term incentive units
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Deferred compensation, expensed	$ 1.2	$ 0.8	$ 5.2	$ 3.4
Deferred compensation, capitalized	0.1	0.6	0.2	1.4
Unearned compensation	11		$ 11		$ 6.9
Expected period to recognize unearned compensation (in years)			2 years 11 months 28 days
Market performance-based awards
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Deferred compensation, expensed	3.1	2.7	$ 10	7.3
Deferred compensation, capitalized	0.3	0.6	0.7	1.9
Unearned compensation	28.4		$ 28.4		24.7
Expected period to recognize unearned compensation (in years)			2 years 1 month 2 days
Restricted stock
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Deferred compensation, expensed	1.5	1.1	$ 4.7	3.3
Deferred compensation, capitalized	1.1	$ 0.8	3.2	$ 2.5
Unearned compensation	$ 23.4		$ 23.4		$ 17.5
Expected period to recognize unearned compensation (in years)			2 years 9 months

Incentive Plan (Summary of Long

Incentive Plan (Summary of Long-Term Incentive Units) (Details)	9 Months Ended
	Sep. 30, 2018$ / sharesshares
Units
Granted (shares)	114,472
Long-term incentive units
Units
Unvested beginning of period (shares)	99,295
Granted (shares)	114,472
Vested (shares)	(49,054)
Cancelled or expired (shares)	(14,275)
Unvested end of period (shares)	150,438
Weighted-Average Grant Date Fair Value
Unvested, beginning of period (in dollars per share) | $ / shares	$ 90.59
Granted (in dollars per share) | $ / shares	101.26
Vested (in dollars per share) | $ / shares	88.97
Cancelled or expired (in dollars per share) | $ / shares	82.85
Unvested, end of period (in dollars per share) | $ / shares	$ 99.49
Minimum | Long-term incentive units
Weighted-Average Grant Date Fair Value
Award vesting period	2 years
Maximum | Long-term incentive units
Weighted-Average Grant Date Fair Value
Award vesting period	4 years

Incentive Plan (Market Performa

Incentive Plan (Market Performance Based Awards) (Details) $ in Millions	Mar. 09, 2018	Mar. 01, 2018	Feb. 27, 2018	Jan. 01, 2018	Feb. 28, 2017	Jan. 01, 2017	Jan. 31, 2018shares	Sep. 30, 2018USD ($)simulationshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (shares)								114,472
Market performance-based awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period								3 years
Number of trials | simulation								100,000
Risk-Free Interest rate	2.42%	2.34%		1.98%	1.43%	1.49%
Fair value of awards | $								$ 96.7
Award requisite service period								4 years
Market performance-based awards | Below Threshold Level
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance threshold percentage								(3.00%)
Vesting percentage								0.00%
Market performance-based awards | Threshold Level
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance threshold percentage								(3.00%)
Vesting percentage								25.00%
Market performance-based awards | Target Level
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance threshold percentage								1.00%
Vesting percentage								50.00%
Market performance-based awards | High Level
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance threshold percentage								5.00%
Vesting percentage								100.00%
Class D Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (shares)								2,165,692
Vested (shares)							363,193
Distribution Equivalent Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested (shares)							36,246
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (shares)								590,569
Vested (shares)							49,707
2015 Performance Grant | Market performance-based awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			50.00%
2015 Performance Grant | Market performance-based awards | First Vesting Period in February
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage								50.00%
2016 Performance Grant | Market performance-based awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period								3 years
2017 Performance Grant | Market performance-based awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period								3 years
2017 Performance Grant | Market performance-based awards | First Vesting Period in February
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage								50.00%
2017 Performance Grant | Market performance-based awards | Second Vesting Period in February
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage								50.00%
2018 Performance Grant | Market performance-based awards | First Vesting Period in February
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage								50.00%
2018 Performance Grant | Market performance-based awards | Second Vesting Period in February
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage								50.00%

Incentive Plan Incentive Plan_2

Incentive Plan Incentive Plan (Assumptions Used) (Details) - Market performance-based awards	Mar. 09, 2018	Mar. 01, 2018	Jan. 01, 2018	Feb. 28, 2017	Jan. 01, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected Stock Price Volatility	22.00%	22.00%	22.00%	23.00%	25.00%
Risk-Free Interest rate	2.42%	2.34%	1.98%	1.43%	1.49%

Incentive Plan (Summary of Rest

Incentive Plan (Summary of Restricted Stock Activity) (Details)	9 Months Ended
	Sep. 30, 2018$ / sharesshares
Units
Granted (shares)	114,472
Restricted stock
Units
Unvested beginning of period (shares)	259,422
Granted (shares)	164,748
Vested (shares)	(92,432)
Cancelled or expired (shares)	(28,510)
Unvested end of period (shares)	303,228
Weighted-Average Grant Date Fair Value
Unvested, beginning of period (in dollars per share) | $ / shares	$ 90.54
Granted (in dollars per share) | $ / shares	101.24
Vested (in dollars per share) | $ / shares	82.96
Cancelled or expired (in dollars per share) | $ / shares	96.69
Unvested, end of period (in dollars per share) | $ / shares	$ 97.21
Restricted stock | Maximum
Weighted-Average Grant Date Fair Value
Award vesting period	4 years

Derivative Instruments (Narrati

Derivative Instruments (Narrative) (Details) $ in Thousands, £ in Millions	9 Months Ended
	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2018GBP (£)instrument	Jul. 01, 2016instrument	Jun. 30, 2016USD ($)
Derivative [Line Items]
Gain (loss) to be reclassified within twelve months	$ 8,500
Proceeds from forward contracts	0	$ 63,956
Designated as Hedging Instrument | Currency forward contracts
Derivative [Line Items]
Number of Instruments | instrument			4	4
Notional amount | £			£ 357.3
Proceeds from forward contracts	64,000
Amount of AOCI to remain in AOCI	$ 26,200
Not Designated as Hedging Instrument | Currency forward contracts
Derivative [Line Items]
Fair value of derivatives					$ 37,800

Derivative Instruments (Outstan

Derivative Instruments (Outstanding Interest Rate Derivatives) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2018USD ($)$ / £$ / $	Dec. 31, 2017USD ($)$ / £$ / $
Digital Realty Trust, L.P. | Unsecured term loan — 5-year
Currently-paying contracts
Debt instrument term	5 years
Digital Realty Trust, L.P. | Unsecured term loan — 7-year
Currently-paying contracts
Debt instrument term	7 years
Digital Realty Trust, L.P. | Unsecured Term Loans | British pound sterling (£)
Currently-paying contracts
Exchange rate | $ / £	1.30	1.35
Digital Realty Trust, L.P. | Unsecured Term Loans | Canadian dollar (CAD)
Currently-paying contracts
Exchange rate | $ / $	0.77	0.80
Interest Rate Swap, 1.611
Currently-paying contracts
Notional Amount	$ 206,000	$ 206,000
Strike Rate	1.611%
Interest Rate Swap, 1.611 | Level 2
Currently-paying contracts
Fair value of derivatives	$ 2,856	1,409
Interest Rate Swap, 1.605
Currently-paying contracts
Notional Amount	$ 54,905	54,905
Strike Rate	1.605%
Interest Rate Swap, 1.605 | Level 2
Currently-paying contracts
Fair value of derivatives	$ 747	374
Interest Rate Swap 1.016
Currently-paying contracts
Notional Amount	$ 75,000	75,000
Strike Rate	1.016%
Interest Rate Swap 1.016 | Level 2
Currently-paying contracts
Fair value of derivatives	$ 3,023	2,260
Interest Rate Swap, 1.164
Currently-paying contracts
Notional Amount	$ 75,000	75,000
Strike Rate	1.164%
Interest Rate Swap, 1.164 | Level 2
Currently-paying contracts
Fair value of derivatives	$ 2,808	1,947
Interest Rate Swap, 1.435
Currently-paying contracts
Notional Amount	$ 300,000	300,000
Strike Rate	1.435%
Interest Rate Swap, 1.435 | Level 2
Currently-paying contracts
Fair value of derivatives	$ 17,829	9,978
Interest Rate Swap, 0.792
Currently-paying contracts
Notional Amount	$ 220,843	229,012
Strike Rate	0.792%
Interest Rate Swap, 0.792 | Level 2
Currently-paying contracts
Fair value of derivatives	$ (24)	(430)
Interest Rate Swap, 0.779
Currently-paying contracts
Notional Amount	$ 76,298	78,357
Strike Rate	0.779%
Interest Rate Swap, 0.779 | Level 2
Currently-paying contracts
Fair value of derivatives	$ 2,960	3,034
Interest Rate Swap
Currently-paying contracts
Notional Amount	1,008,046	1,018,274
Interest Rate Swap | Level 2
Currently-paying contracts
Fair value of derivatives	$ 30,199	$ 18,572

Fair Value of Financial Instr_3

Fair Value of Financial Instruments (Estimated Fair Value And Carrying Amounts) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
5.875% notes due 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate	5.875%
3.400% notes due 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate	3.40%
3.950% notes due 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate	3.95%
3.625% notes due 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate	3.625%
4.750% notes due 2023
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate	4.75%
2.750% notes due 2023
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate	2.75%
2.625% notes due 2024
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate	2.625%
2.750% notes due 2024
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate	2.75%
4.750% notes due 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate	4.75%
4.250% notes due 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate	4.25%
Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value of long-term debt	$ 9,338,986	$ 9,066,434
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value of long-term debt	9,226,611	8,698,464
Global revolving credit facility, net
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deferred financing costs	4,700	7,200
Unsecured Term Loans
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deferred financing costs	3,700	4,800
Unsecured Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value of long-term debt	16,500	18,500
Deferred financing costs	$ 38,300	37,800
Unsecured Senior Notes | 3.400% notes due 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate	3.40%
Unsecured Senior Notes | 3.950% notes due 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate	3.95%
Unsecured Senior Notes | 3.625% notes due 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate	3.625%
Unsecured Senior Notes | 2.625% notes due 2024
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate	2.625%
Unsecured Senior Notes | 2.750% notes due 2024
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate	2.75%
Unsecured Senior Notes | 4.750% notes due 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate	4.75%
Mortgage Loans
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deferred financing costs	$ 0	0
Level 2 | Global revolving credit facility, net | Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Lines of credit	594,983	558,191
Level 2 | Global revolving credit facility, net | Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Lines of credit	594,983	558,191
Level 2 | Unsecured Term Loans | Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Lines of credit	1,356,702	1,425,117
Level 2 | Unsecured Term Loans | Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Lines of credit	1,356,702	1,425,117
Level 2 | Unsecured Senior Notes | Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unsecured senior notes	7,280,877	6,976,603
Level 2 | Unsecured Senior Notes | Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unsecured senior notes	7,168,825	6,608,545
Level 2 | Mortgage Loans | Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage Loans	106,424	106,523
Level 2 | Mortgage Loans | Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage Loans	$ 106,101	$ 106,611

Commitments and Contingencies (

Commitments and Contingencies (Details) $ in Millions	Sep. 30, 2018USD ($)
Commitments and Contingencies Disclosure [Abstract]
Reimbursable amount of commitments related to construction contracts	$ 5.7
Commitments related to construction contracts	$ 428.3

Subsequent Events (Details)

Subsequent Events (Details) ¥ in Billions	Oct. 24, 2018USD ($)extension	Sep. 30, 2018	Oct. 24, 2018JPY (¥)	Jan. 15, 2016USD ($)
Global Revolving Credit Facility 2018 | Subsequent Event Type
Subsequent Event [Line Items]
Credit facility, maximum borrowing capacity	$ 2,350,000,000
Number of extension options | extension	2
Debt instrument, extension term	6 months
Credit facility, maximum borrowing capacity, subject to receipt of lender commitments and other conditions	$ 1,250,000,000
Global Revolving Credit Facility
Subsequent Event [Line Items]
Credit facility, maximum borrowing capacity				$ 2,000,000,000
Yen Revolving Credit Facility | Subsequent Event Type
Subsequent Event [Line Items]
Credit facility, maximum borrowing capacity	296,500,000		¥ 33.3
Credit facility, maximum borrowing capacity, subject to receipt of lender commitments and other conditions	831,100,000		¥ 93.3
Unsecured Term Loan, 5 Year, 2023 | Subsequent Event Type
Subsequent Event [Line Items]
Credit facility, maximum borrowing capacity	$ 300,000,000
Debt instrument term	5 years
Unsecured Term Loan, 5 Year, 2024 | Subsequent Event Type
Subsequent Event [Line Items]
Credit facility, maximum borrowing capacity	$ 512,000,000
Number of extension options | extension	2
Debt instrument, extension term	6 months
Debt instrument term	5 years
Unsecured Term Loans
Subsequent Event [Line Items]
Credit facility, maximum borrowing capacity				$ 1.55
Eurodollar
Subsequent Event [Line Items]
Interest rate basis spread		100.00%
Base Rate
Subsequent Event [Line Items]
Interest rate basis spread		0.00%