Basis Points Extension Fee On Total Commitment

No definition available.

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- Definition

Consolidated Total Indebtedness To Gross Assets Value Ratio

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Consolidated Total Indebtedness To Gross Assets Value Ratio After Material Acquisition

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Facility amount available for Letters of Credit

+ References

No definition available.

+ Details

Name:	dft_FacilityAmountAvailableForLettersOfCredit
Namespace Prefix:	dft_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Fixed charge coverage ratio.

+ References

No definition available.

+ Details

Name:	dft_FixedChargeCoverageRatio
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Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- Definition

Income from unencumbered assets to unsecured debt.

+ References

No definition available.

+ Details

Name:	dft_IncomeFromUnencumberedAssetsToUnsecuredDebt
Namespace Prefix:	dft_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Income from Unencumbered Assets To Unsecured Debt After Material Acquisition

+ References

No definition available.

+ Details

Name:	dft_IncomefromUnencumberedAssetsToUnsecuredDebtAfterMaterialAcquisition
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of equity offerings and interests in operating partnerships to be added to tangible net worth threshold.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Tangible net worth amount.

+ References

No definition available.

+ Details

Name:	dft_TangibleNetWorthAmount
Namespace Prefix:	dft_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Unhedged Variable Rate Debt To Gross Asset Value Ratio

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No definition available.

+ Details

Name:	dft_UnhedgedVariableRateDebtToGrossAssetValueRatio
Namespace Prefix:	dft_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

UnsecuredDebtToUnencumberedAssetsAfterMaterialAcquistion

+ References

No definition available.

+ Details

Name:	dft_UnsecuredDebtToUnencumberedAssetsAfterMaterialAcquistion
Namespace Prefix:	dft_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Unsecured Debt To Unencumbered Assets

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_DebtInstrumentAxis=us-gaap_RevolvingCreditFacilityMember
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Balance Type:
Period Type:

- Details

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- Details

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- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_ForeignLineOfCreditMember
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4. Debt Unsecured Credit Facility (Details) $ in Thousands, CAD in Millions	3 Months Ended
	Mar. 31, 2017 USD ($)	Mar. 31, 2017 CAD	Mar. 31, 2017 USD ($)	Dec. 31, 2016 CAD	Dec. 31, 2016 USD ($)
Debt Instrument [Line Items]
Line of Credit Facility, Current Borrowing Capacity			$ 750,000
Line of Credit Facility, Maximum Borrowing Capacity			1,250,000
Basis Points Extension Fee On Total Commitment	7.5
Facility amount available for Letters of Credit	$ 35,000
Letters of Credit Outstanding, Amount			0
Line of credit			197,819		$ 50,926
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Jul. 25, 2020
Revolving Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Unsecured Debt To Unencumbered Assets	60.00%
Unsecured Debt To Unencumbered Assets After Material Acquisition	65.00%
Ratio of Total Indebtedness To Gross Assets Value	60.00%
Ratio of Total Indebtedness To Gross Assets Value After Material Acquisition	65.00%
Unhedged Variable Rate Debt To Gross Asset Value Ratio	30.00%
Revolving Credit Facility [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Income from Unencumbered Assets To Unsecured Debt	12.50%
Income from Unencumbered Assets To Unsecured Debt After Material Acquisition	10.00%
Fixed Charge Coverage Ratio	1.70
Tangible Net Worth Amount			$ 2,300,000
Percentage Of Equity Offerings And Interests In Operating Partnerships To Be Added To Tangible Net Worth Threshold	75.00%
Foreign Line of Credit [Member]
Debt Instrument [Line Items]
Line of credit \| CAD		CAD 77
Foreign Line of Credit [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Current Borrowing Capacity				CAD 250	$ 185,000