2. Significant Accounting Policies Schedule of Above and Below Market Lease Intangibles (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Accounting Policies [Abstract]
Lease contracts above market value	$ 23,100	$ 23,100
Accumulated amortization	(15,321)	(15,046)
Lease contracts above market value, net	7,779us-gaap_FiniteLivedIntangibleAssetsNet	8,054us-gaap_FiniteLivedIntangibleAssetsNet
Lease contracts below market value	39,375dft_OffMarketLeaseUnfavorableGross	39,375dft_OffMarketLeaseUnfavorableGross
Accumulated amortization	(33,206)	(32,338)
Lease contracts below market value, net	$ 6,169us-gaap_OffMarketLeaseUnfavorable	$ 7,037us-gaap_OffMarketLeaseUnfavorable

Off Market Lease Unfavorable Accumulated Amortization

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- Definition

Off Market Lease Unfavorable Gross

+ References

No definition available.

+ Details

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- Details

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- Definition

This element represents the identifiable intangible asset established upon acquisition based on a favorable difference between the terms of an acquired lease and the current market terms for that lease at the acquisition date.

+ 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 210.5-02.15)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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Namespace Prefix:	us-gaap_
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- Definition

This element represents a liability associated with the acquisition of an off-market lease when the terms of the lease are unfavorable to the market terms for the lease at the date of acquisition.

+ 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 210.5-02.24)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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