Maximum period of hedging exposure to the variability in future cash flows for forecasted transactions (in years)

No definition available.

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- Definition

Number of interest rate swap agreements entered into

+ References

No definition available.

+ Details

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- Definition

Portion of Building Leased (percentage)

+ References

No definition available.

+ Details

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- Definition

Term of Lease Signed (in years)

+ References

No definition available.

+ Details

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- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

+ Details

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- Definition

Average fixed interest rate related to the group of interest rate derivatives.

+ References

No definition available.

+ Details

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

+ Details

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Period Type:	instant

- Definition

Net rentable area for properties owned.

+ References

No definition available.

+ Details

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- Definition

The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

+ 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 (b)

-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3213-108585

+ Details

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- Details

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- Details

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- Details

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Subsequent Events subsequent Events (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		1 Months Ended	0 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	May 08, 2015 swaps Y	May 08, 2015
Subsequent Event [Line Items]
Payments to Enter into a Joint Venture Agreement	$ 2,444	$ 0
Interest Rate Swap [Member]
Subsequent Event [Line Items]
Number of interest rate swap agreements entered into (swap contracts)	5
Maximum period of hedging exposure to the variability in future cash flows for forecasted transactions (in years)	10
Average Fixed Interest Rate	2.492%
Notional Amount	250,000
Interest Rate Swap [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Number of interest rate swap agreements entered into (swap contracts)			3
Maximum period of hedging exposure to the variability in future cash flows for forecasted transactions (in years)			10
Average Fixed Interest Rate			2.344%	2.344%
Notional Amount			75,000	75,000
1265 Main Street [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Net Rentable Area (in sf)			120,000	120,000
Term of Lease Signed (in years)			15	15
Portion of Building Leased (percentage)			100.00%	100.00%
1265 Main Street [Member] \| joint venture partner [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Payments to Enter into a Joint Venture Agreement				9,400
Ownership Percentage			50.00%	50.00%
1265 Main Street [Member] \| Company [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Ownership Percentage			50.00%	50.00%
1265 Main Street [Member] \| Maximum [Member] \| Company [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Payments to Enter into a Joint Venture Agreement				$ 9,400