Equity Method Investment, Ownership Percentage by Third Party

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- Definition

Gain (Loss) Change In Control And Other

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- Definition

Mortgage Loans On Real Estate, Accrued Interest

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- Definition

Area of a real estate property.

+ References

No definition available.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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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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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of gain (loss) on sale or disposal of an equity method investment.

+ References

No definition available.

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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

The carrying amount of the outstanding balance due under the mortgage loan.

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

The carrying amount of mortgage loans on real estate that were sold during the reporting period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
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- Definition

The number of businesses acquired by the entity during the period.

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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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-Name Accounting Standards Codification
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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.

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No definition available.

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Investments in and Advances to Unconsolidated Affiliates - Core Portfolio (Details) $ in Thousands				1 Months Ended	3 Months Ended	12 Months Ended
	Nov. 16, 2017 USD ($)	May 01, 2017 USD ($)	Jan. 04, 2017 USD ($) ft²	Apr. 29, 2016 USD ($)	Dec. 31, 2017 USD ($) ft²	Dec. 31, 2017 USD ($) ft² property	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Mar. 31, 2016
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage									65.00%
Purchase Price						$ 254,532	$ 756,842
Notes receivable, net					$ 153,829	153,829	276,163
Gain on change in control and other					5,600	5,571	0	$ 1,596
Core Portfolio
Schedule of Equity Method Investments [Line Items]
Purchase Price						42,800	519,592
Notes receivable, net					101,695	101,695	216,400
Equity method investments					$ 216,583	$ 216,583	165,031
Core Portfolio \| Crossroads
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage					49.00%	49.00%
Square footage of real estate property (in square feet) \| ft²					311,000	311,000
Core Portfolio \| Georgetown Portfolio
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage					50.00%	50.00%
Square footage of real estate property (in square feet) \| ft²					28,000	28,000
Equity method investments					$ 3,479	$ 3,479	4,287
Core Portfolio \| Gotham Plaza
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage					49.00%	49.00%
Square footage of real estate property (in square feet) \| ft²					123,000	123,000
Percentage of voting interests acquired					49.00%	49.00%
Equity method investments					$ 29,416	$ 29,416	29,421
Core Portfolio \| Renaissance Portfolio
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage					20.00%	20.00%
Square footage of real estate property (in square feet) \| ft²					213,000	213,000
Percentage of voting interests acquired			20.00%
Number of businesses acquired \| property						18
Equity method investments					$ 35,041	$ 35,041	$ 36,437
Core Portfolio \| Brandywine Portfolio
Schedule of Equity Method Investments [Line Items]
Square footage of real estate property (in square feet) \| ft²					1,000,000	1,000,000
Repayments of debt				$ 140,000
Note receivable exchanged		$ 16,000
Notes receivable, net		153,400			$ 60,700	$ 60,700
Note receivable accrued interest		$ 300
Core Portfolio \| Town Center
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	22.22%				61.11%	61.11%
Equity method investment, ownership percentage by third party	38.89%				38.89%	38.89%
Equity method investments	$ 61,600
Gain on equity method investment	$ 34,500
Core Portfolio \| Market Square
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	22.22%	61.11%
Equity method investment, ownership percentage by third party	38.89%	38.89%
Equity method investments		$ 16,300
Gain on equity method investment		$ 9,800
Core Portfolio \| Chicago, IL
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage					88.43%	88.43%
Square footage of real estate property (in square feet) \| ft²					87,000	87,000
Core Portfolio \| Alexandria, Virginia \| Renaissance Portfolio
Schedule of Equity Method Investments [Line Items]
Square footage of real estate property (in square feet) \| ft²			6,200
Purchase Price			$ 3,000
Number of businesses acquired \| property						2
Core Portfolio \| Washington D.C. \| Renaissance Portfolio
Schedule of Equity Method Investments [Line Items]
Number of businesses acquired \| property						16
Exchange Transaction One \| Core Portfolio \| Brandywine Portfolio
Schedule of Equity Method Investments [Line Items]
Note receivable exchanged	$ 16,000
Note receivable accrued interest	600
Exchange Transaction Two \| Core Portfolio \| Brandywine Portfolio
Schedule of Equity Method Investments [Line Items]
Note receivable exchanged	60,700
Note receivable accrued interest	$ 900