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=63488584&loc=d3e20235-122688

+ Details

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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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- 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 ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2016 USD ($)	Nov. 10, 2016 a	Nov. 30, 2014 ft²
Investment in Real Estate
Land	$ 74,819		$ 100,258
Buildings and Improvements	1,037,127		1,472,580
Construction in progress	183,189		70,738
Total investments in real estate			1,643,576
Gain (loss) on real estate disposal	$ 36	$ 1,208
Area of land disposed of in sale \| a				21.75
Boston
Investment in Real Estate
Land			5,154
Buildings and Improvements			96,470
Construction in progress			167
Total investments in real estate			101,791
Chicago
Investment in Real Estate
Land			5,493
Buildings and Improvements			98,872
Construction in progress			6,877
Total investments in real estate			111,242
Denver
Investment in Real Estate
Buildings and Improvements			5,377
Construction in progress			5,955
Total investments in real estate			11,332
Los Angeles
Investment in Real Estate
Land			28,467
Buildings and Improvements			235,073
Construction in progress			5,987
Total investments in real estate			269,527
Miami
Investment in Real Estate
Land			728
Buildings and Improvements			10,499
Total investments in real estate			11,227
New York
Investment in Real Estate
Land			2,388
Buildings and Improvements			128,078
Construction in progress			38,632
Total investments in real estate			169,098
Northern Virginia
Investment in Real Estate
Land			26,642
Buildings and Improvements			292,173
Construction in progress			12,085
Total investments in real estate			330,900
San Francisco Bay
Investment in Real Estate
Land			31,386
Buildings and Improvements			606,038
Construction in progress			1,035
Total investments in real estate			$ 638,459
BO1 Somerville MA
Investment in Real Estate
Gain (loss) on real estate disposal		$ 1,200
Area of land disposed of in sale \| ft²					52,248