Area of land held.

No definition available.

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- Definition

The current amount of expenditures for a real estate project that has not yet been completed.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.10)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Phase
-URI http://asc.fasb.org/extlink&oid=49177889

+ Details

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- Definition

Aggregate of the carrying amounts as of the balance sheet date of investments in building and building improvements.

+ References

+ Details

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- Definition

Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 4
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6812-107765

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.13)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Revenue from the sale of land in the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Amount of real estate investment property which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

+ References

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Investment in Real Estate (Details) $ in Thousands	12 Months Ended
Investment in Real Estate (Details) $ in Thousands	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Nov. 30, 2014 ft²
Investment in Real Estate
Land	$ 74,819	$ 78,983
Buildings and Improvements	1,037,127	888,966
Construction in progress	183,189	178,599
Total investments in real estate	1,295,135
Gain on real estate disposal	36	1,208
Boston
Investment in Real Estate
Land	5,154
Buildings and Improvements	82,373
Construction in progress	10,203
Total investments in real estate	97,730
Chicago
Investment in Real Estate
Land	5,493
Buildings and Improvements	93,861
Construction in progress	1,582
Total investments in real estate	100,936
Denver
Investment in Real Estate
Buildings and Improvements	4,349
Construction in progress	68
Total investments in real estate	4,417
Los Angeles
Investment in Real Estate
Land	28,467
Buildings and Improvements	207,337
Construction in progress	12,957
Total investments in real estate	248,761
Miami
Investment in Real Estate
Land	728
Buildings and Improvements	10,418
Construction in progress	1
Total investments in real estate	11,147
New York
Investment in Real Estate
Land	2,388
Buildings and Improvements	125,914
Construction in progress	38,371
Total investments in real estate	166,673
Northern Virginia
Investment in Real Estate
Land	9,623
Buildings and Improvements	190,541
Construction in progress	54,001
Total investments in real estate	254,165
San Francisco Bay
Investment in Real Estate
Land	22,966
Buildings and Improvements	322,334
Construction in progress	66,006
Total investments in real estate	$ 411,306
BO1 Somerville MA
Investment in Real Estate
Area of land disposed of in sale \| ft²			52,248
Gain on real estate disposal		$ 1,200