Debt Instrument, Extended Maturity Period

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- Definition

Debt Instrument, Number of One-Year Maturity Date Extension Option

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- Definition

Expected Total Joint Venture Development Cost

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- Definition

Length of Lease

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No definition available.

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- Definition

Represents RSF occupied as a percentage of total RSF

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No definition available.

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The amount of rentable square feet related to real estate operating properties.

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- Definition

Area of a real estate property.

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- Definition

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

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No definition available.

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- Definition

Minimum contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 22
-Article 5

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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.

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-Name Accounting Standards Codification
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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.

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- Definition

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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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- Definition

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

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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.

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Investments in unconsolidated real estate joint ventures (Details) $ in Millions	1 Months Ended	12 Months Ended
	Sep. 30, 2014 USD ($)	Dec. 31, 2015 USD ($) ft² Extension_Option
Schedule of Equity Method Investments [Line Items]
Area of Real Estate Property \| ft²		20,073,784
Payments to acquired real estate property		$ 438.1
Greater Boston \| Longwood
Schedule of Equity Method Investments [Line Items]
Area of Real Estate Property \| ft²		413,799
Expected Total Joint Venture Development Cost		$ 350.0
Rentable Square Footage of Real Estate Property, Operating Properties \| ft²		259,859
Real estate occupancy percentage		63.00%
Equity method of accounting - unconsolidated joint ventures		$ 50.2
Greater Boston \| Equity Method Investee \| Longwood
Schedule of Equity Method Investments [Line Items]
Equity interest percentage (in percent)		27.50%
San Francisco Bay Area \| 1455/1515 Third Street
Schedule of Equity Method Investments [Line Items]
Real estate occupancy percentage		100.00%
Equity method of accounting - unconsolidated joint ventures		$ 77.0
Length of Lease		15 years
Aggregate Commitments \| Greater Boston \| Longwood
Schedule of Equity Method Investments [Line Items]
Long-term Construction Loan		$ 213.2
Outstanding Balance \| Greater Boston \| Longwood
Schedule of Equity Method Investments [Line Items]
Long-term Construction Loan		177.2
Remaining commitments \| Greater Boston \| Longwood
Schedule of Equity Method Investments [Line Items]
Long-term Construction Loan		$ 36.0
Secured Debt from Bank Maturing on 1 April 2017 \| Longwood
Schedule of Equity Method Investments [Line Items]
Debt Instrument, Number of One-Year Maturity Date Extension Option \| Extension_Option		2
Debt Instrument, Extended Maturity Period		1 year
Construction Loans \| Longwood
Schedule of Equity Method Investments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum		5.25%
Construction Loans \| LIBOR \| Longwood
Schedule of Equity Method Investments [Line Items]
Debt Instrument, Basis Spread on Variable Rate		3.75%
1455/1515 Third Street \| San Francisco Bay Area
Schedule of Equity Method Investments [Line Items]
Area of Real Estate Property \| ft²		422,980
Payments to acquired real estate property	$ 125.0
Alexandria Real Estate Equities, Inc. \| San Francisco Bay Area \| 1455/1515 Third Street
Schedule of Equity Method Investments [Line Items]
Equity interest percentage (in percent)		51.00%
Uber Technologies, Inc. \| San Francisco Bay Area \| 1455/1515 Third Street
Schedule of Equity Method Investments [Line Items]
Equity interest percentage (in percent)		49.00%