13. Supplemental Consolidating Financial Data for Subsidiary Guarantors of the Unsecured Notes Supplemental Consodlidating Statements of Cash Flows (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Supplemental Consolidating Statements Of Cash Flows [Line Items]
Net Cash Provided by (Used in) Operating Activities	$ 85,787	$ 58,589
Investments in real estate – development	(20,516)	(35,752)
Interest capitalized for real estate under development	(504)	(1,533)
Improvements to real estate	(4,357)	(1,677)
Additions to non-real estate property	(24)	(55)
Net cash used in investing activities	(25,401)	(39,017)
Proceeds from line of credit	72,000	15,000
Repayments of line of credit	(30,000)	(35,000)
Repayments of Secured Debt	(1,300)	(2,600)
Proceeds from mortgage notes payable	115,000	0
Lump sum payoffs of mortgage notes payable	(138,300)	0
Exercises of stock options	0	868
Payments of financing costs	(3,036)	(2,081)
Payments for Repurchase of Common Stock	(37,792)	0
Net cash provided by financing activities	(69,591)	6,803
Net increase (decrease) in cash and cash equivalents	(9,205)	26,375
Cash and cash equivalents, beginning	23,578	14,402
Cash and cash equivalents, ending	14,373	40,777
DuPont Fabros Technology, L.P. [Member]
Supplemental Consolidating Statements Of Cash Flows [Line Items]
Net Cash Provided by (Used in) Operating Activities	85,787	58,589
Investments in real estate – development	(20,516)	(35,752)
Investments in affiliates	0	0
Interest capitalized for real estate under development	(504)	(1,533)
Improvements to real estate	(4,357)	(1,677)
Additions to non-real estate property	(24)	(55)
Net cash used in investing activities	(25,401)	(39,017)
Issuance of preferred units, net of offering costs		62,694
Proceeds from line of credit	72,000	15,000
Repayments of line of credit	(30,000)	(35,000)
Repayments of Secured Debt	(1,300)	(2,600)
Proceeds from mortgage notes payable	115,000	0
Lump sum payoffs of mortgage notes payable	(138,300)	0
Exercises of stock options	0	868
Payments of financing costs	(3,036)	(2,081)
Payments for Repurchase of Common Stock	(37,792)	0
Payments of Distributions to Affiliates	(46,163)	(32,069)
Net cash provided by financing activities	(69,591)	6,812
Net increase (decrease) in cash and cash equivalents	(9,205)	26,384
Cash and cash equivalents, beginning	19,282	10,097
Cash and cash equivalents, ending	10,077	36,481
DuPont Fabros Technology, L.P. [Member] | Operating Partnership [Member]
Supplemental Consolidating Statements Of Cash Flows [Line Items]
Net Cash Provided by (Used in) Operating Activities	(26,379)	(26,400)
Investments in real estate – development	(13)	(22)
Investments in affiliates	60,306	43,729
Interest capitalized for real estate under development	0	0
Improvements to real estate	0	0
Additions to non-real estate property	(6)	(17)
Net cash used in investing activities	60,287	43,690
Issuance of preferred units, net of offering costs		62,694
Proceeds from line of credit	72,000	15,000
Repayments of line of credit	(30,000)	(35,000)
Repayments of Secured Debt	0	0
Proceeds from mortgage notes payable	0
Lump sum payoffs of mortgage notes payable	0
Exercises of stock options		868
Payments of financing costs	(1,329)	(2,081)
Payments for Repurchase of Common Stock	(37,792)
Payments of Distributions to Affiliates	(46,163)	(32,069)
Net cash provided by financing activities	(43,284)	9,412
Net increase (decrease) in cash and cash equivalents	(9,376)	26,702
Cash and cash equivalents, beginning	18,240	9,174
Cash and cash equivalents, ending	8,864	35,876
DuPont Fabros Technology, L.P. [Member] | Subsidiary Guarantors [Member]
Supplemental Consolidating Statements Of Cash Flows [Line Items]
Net Cash Provided by (Used in) Operating Activities	104,102	78,475
Investments in real estate – development	(13,649)	(26,409)
Investments in affiliates	53,516	(46,188)
Interest capitalized for real estate under development	(33)	(1,533)
Improvements to real estate	(4,260)	(1,677)
Additions to non-real estate property	(18)	(20)
Net cash used in investing activities	35,556	(75,827)
Issuance of preferred units, net of offering costs		0
Proceeds from line of credit	0	0
Repayments of line of credit	0	0
Repayments of Secured Debt	(1,300)	(2,600)
Proceeds from mortgage notes payable	0
Lump sum payoffs of mortgage notes payable	(138,300)
Exercises of stock options		0
Payments of financing costs	(4)	0
Payments for Repurchase of Common Stock	0
Payments of Distributions to Affiliates	0	0
Net cash provided by financing activities	(139,604)	(2,600)
Net increase (decrease) in cash and cash equivalents	54	48
Cash and cash equivalents, beginning	361	196
Cash and cash equivalents, ending	415	244
DuPont Fabros Technology, L.P. [Member] | Subsidiary Non-Guarantors [Member]
Supplemental Consolidating Statements Of Cash Flows [Line Items]
Net Cash Provided by (Used in) Operating Activities	8,064	6,514
Investments in real estate – development	(6,854)	(9,321)
Investments in affiliates	(113,822)	2,459
Interest capitalized for real estate under development	(471)	0
Improvements to real estate	(97)	0
Additions to non-real estate property	0	(18)
Net cash used in investing activities	(121,244)	(6,880)
Issuance of preferred units, net of offering costs		0
Proceeds from line of credit	0	0
Repayments of line of credit	0	0
Repayments of Secured Debt	0	0
Proceeds from mortgage notes payable	115,000
Lump sum payoffs of mortgage notes payable	0
Exercises of stock options		0
Payments of financing costs	(1,703)	0
Payments for Repurchase of Common Stock	0
Payments of Distributions to Affiliates	0	0
Net cash provided by financing activities	113,297	0
Net increase (decrease) in cash and cash equivalents	117	(366)
Cash and cash equivalents, beginning	681	727
Cash and cash equivalents, ending	798	361
DuPont Fabros Technology, L.P. [Member] | Eliminations [Member]
Supplemental Consolidating Statements Of Cash Flows [Line Items]
Net Cash Provided by (Used in) Operating Activities	0	0
Investments in real estate – development	0	0
Investments in affiliates	0	0
Interest capitalized for real estate under development	0	0
Improvements to real estate	0	0
Additions to non-real estate property	0	0
Net cash used in investing activities	0	0
Issuance of preferred units, net of offering costs		0
Proceeds from line of credit	0	0
Repayments of line of credit	0	0
Repayments of Secured Debt	0	0
Proceeds from mortgage notes payable	0
Lump sum payoffs of mortgage notes payable	0
Exercises of stock options		0
Payments of financing costs	0	0
Payments for Repurchase of Common Stock	0
Payments of Distributions to Affiliates	0	0
Net cash provided by financing activities	0	0
Net increase (decrease) in cash and cash equivalents	0	0
Cash and cash equivalents, beginning	0	0
Cash and cash equivalents, ending	$ 0	$ 0