The minimum interest rate to be applied to the debt instrument over the course of its life.

No definition available.

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- Definition

Expected Total Joint Venture Development Cost

+ References

No definition available.

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- Definition

Length of Lease

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No definition available.

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- Definition

Pre-leased RSF as a Percentage of Total Project RSF

+ References

No definition available.

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- Definition

Area of a real estate property.

+ References

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

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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)

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ 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 210.5-02.12)

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-Section 45

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This element represents the current and noncurrent portions of a long-term real estate loan with an initial maturity beyond one year or beyond the normal operating cycle, if longer, to finance building costs. The funds are disbursed as needed or in accordance with a prearranged plan; generally, a portion of the funds is disbursed at inception and the remainder as construction progresses. The money is repaid on completion of the project (generally one to seven years), usually from the proceeds of a mortgage loan. The rate is normally higher than the prime rate, and there is usually an origination fee. The effective yield on these loans tends to be high, and the lender has a security interest in the real property.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

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-Subparagraph (SX 210.9-03.16)

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-Subparagraph (SX 210.5-02.19,20,22)

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- Definition

The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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-Section 45

-Paragraph 13

-Subparagraph (b)

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Investments in real estate, net Investment in unconsolidated entity (Details) (USD $)			9 Months Ended								9 Months Ended	0 Months Ended
	Sep. 30, 2014 sqft	Dec. 31, 2013	Sep. 30, 2014 Debt Instrument, Variable Rate Base [Domain] Greater Boston market Equity Method Investee	Sep. 30, 2014 Debt Instrument, Variable Rate Spread [Member] Greater Boston market Equity Method Investee	Sep. 30, 2014 Debt Instrument, Variable Rate Floor [Member] Greater Boston market Equity Method Investee	Sep. 30, 2014 Longwood [Member] Greater Boston market sqft	Sep. 30, 2014 Longwood [Member] Greater Boston market Equity Method Investee	Sep. 30, 2014 Longwood [Member] Aggregate Commitments [Member] Greater Boston market	Sep. 30, 2014 Longwood [Member] Outstanding Balance [Member] Greater Boston market	Sep. 30, 2014 Longwood [Member] Remaining Commitments [Member] Greater Boston market	Sep. 30, 2014 1455/1515 Third Street [Member] San Franciso Bay Area [Member] sqft	Apr. 18, 2014 1455/1515 Third Street [Member] San Francisco, California [Member]	Sep. 30, 2014 Alexandria [Member] 1455/1515 Third Street [Member] San Francisco, California [Member]	Sep. 30, 2014 Uber Technologies, Inc. [Member] 1455/1515 Third Street [Member] San Francisco, California [Member]
Schedule of Equity Method Investments [Line Items]
Equity interest percentage (in percent)							27.50%						51.00%	49.00%
Area of Real Estate Property	18,458,379					413,536					422,980
Payments to acquire real estate property												$ 125,000,000
Expected Total Joint Venture Development Cost						350,000,000
Pre-leased RSF as a Percentage of Total RSF						37.00%					100.00%
Length of Lease											15 years
Equity Method Investments	114,168,000	46,644,000				48,524,000					65,644,000
Long-term Construction Loan								$ 213,200,000	$ 143,500,000	$ 69,700,000
Base rate			LIBOR
Applicable margin (as a percent)				3.75%
Debt Instrument, Interest Rate Floor					5.25%