Area Owned by Company of Undeveloped Parcels Of Land

No definition available.

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- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

The gain (loss) resulting from the sale of a disposal group that is not a discontinued operation. It is included in income from continuing operations before income taxes in the income statement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 45

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=8077374&loc=d3e2443-110228

+ Details

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- Definition

Net rentable area for properties owned.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash outflow from the acquisition of real estate intended to generate income for the owner; excludes land acquired for use by the owner.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

+ Details

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Balance Type:	credit
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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Subsequent Events (Details) (USD $)	3 Months Ended		0 Months Ended
Subsequent Events (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014	Apr. 06, 2015	Apr. 24, 2015	Apr. 09, 2015 sqft
Subsequent Event [Line Items]
Net gain on disposition of real estate	$ 9,019,000	$ 0
Subsequent Event [Member]
Subsequent Event [Line Items]
Area Owned by Company of Undeveloped Parcels Of Land			0.8
Payments to acquire land			20,000,000
Delaware Corporate Center I and II and Christiana Corporate Center [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Sales of Real Estate				50,100,000
Net gain on disposition of real estate				1,700,000
Lake Merritt Tower [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Sales of Real Estate					$ 65,000,000
Net Rentable Area					204,336
Delaware Corporate Center I & II [Member]
Subsequent Event [Line Items]
Net Rentable Area	200,275
Number of Real Estate Properties	2
Delaware Corporate Center I & II [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Net Rentable Area				200,275
Number of Real Estate Properties				2
Christiana Corporate Center [Member]
Subsequent Event [Line Items]
Net Rentable Area	284,907
Number of Real Estate Properties	3
Christiana Corporate Center [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Net Rentable Area				284,907
Number of Real Estate Properties				3