Real Estate Investments Business Acquisitions (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Business Acquisition [Line Items]
Purchase Price	$ 16,115	$ 123,230
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	0	9,700
Off-Market Favorable Lease [Member]
Business Acquisition [Line Items]
Intangible assets	941	9,929
Off-Market Lease, Unfavorable [Member]
Business Acquisition [Line Items]
Intangible assets	$ 358	$ 6,123
Pablo Plaza [Member]
Business Acquisition [Line Items]
Date Purchased	Jan. 08, 2019
Property Name	Pablo Plaza (1)
City/State	Jacksonville, FL
Business Acquisition, Percentage of Voting Interests Acquired	100.00%
Purchase Price	$ 600
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	0
Pablo Plaza [Member] \| Off-Market Favorable Lease [Member]
Business Acquisition [Line Items]
Intangible assets	0
Pablo Plaza [Member] \| Off-Market Lease, Unfavorable [Member]
Business Acquisition [Line Items]
Intangible assets	$ 0
Melrose Market [Member]
Business Acquisition [Line Items]
Date Purchased	Feb. 08, 2019
Property Name	Melrose Market
City/State	Seattle, WA
Business Acquisition, Percentage of Voting Interests Acquired	100.00%
Purchase Price	$ 15,515
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	0
Melrose Market [Member] \| Off-Market Favorable Lease [Member]
Business Acquisition [Line Items]
Intangible assets	941
Melrose Market [Member] \| Off-Market Lease, Unfavorable [Member]
Business Acquisition [Line Items]
Intangible assets	$ 358
Metuchen [Member]
Business Acquisition [Line Items]
Date Purchased		Jan. 05, 2018
Property Name		Metuchen
City/State		Metuchen, NJ
Business Acquisition, Percentage of Voting Interests Acquired		20.00%
Purchase Price		$ 33,830
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities		0
Metuchen [Member] \| Off-Market Favorable Lease [Member]
Business Acquisition [Line Items]
Intangible assets		3,147
Metuchen [Member] \| Off-Market Lease, Unfavorable [Member]
Business Acquisition [Line Items]
Intangible assets		$ 1,905
Hewlett Crossing I & II [Member]
Business Acquisition [Line Items]
Date Purchased		Jan. 10, 2018
Property Name		Hewlett Crossing I & II
City/State		Hewlett, NY
Business Acquisition, Percentage of Voting Interests Acquired		100.00%
Purchase Price		$ 30,900
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities		9,700
Hewlett Crossing I & II [Member] \| Off-Market Favorable Lease [Member]
Business Acquisition [Line Items]
Intangible assets		3,114
Hewlett Crossing I & II [Member] \| Off-Market Lease, Unfavorable [Member]
Business Acquisition [Line Items]
Intangible assets		$ 1,868
Ballard Blocks I [Member]
Business Acquisition [Line Items]
Date Purchased		Jan. 02, 2018
Property Name		Ballard in Blocks I
City/State		Seattle, WA
Business Acquisition, Percentage of Voting Interests Acquired		49.90%
Purchase Price		$ 54,500
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities		0
Ballard Blocks I [Member] \| Off-Market Favorable Lease [Member]
Business Acquisition [Line Items]
Intangible assets		3,668
Ballard Blocks I [Member] \| Off-Market Lease, Unfavorable [Member]
Business Acquisition [Line Items]
Intangible assets		$ 2,350
Ballard Blocks II [Member]
Business Acquisition [Line Items]
Date Purchased		Jan. 02, 2018
Property Name		Ballard in Blocks II
City/State		Seattle, WA
Business Acquisition, Percentage of Voting Interests Acquired		49.90%
Purchase Price		$ 4,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities		0
Ballard Blocks II [Member] \| Off-Market Favorable Lease [Member]
Business Acquisition [Line Items]
Intangible assets		0
Ballard Blocks II [Member] \| Off-Market Lease, Unfavorable [Member]
Business Acquisition [Line Items]
Intangible assets		$ 0

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Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.

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Name of the acquired entity.

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

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Amount of liabilities assumed at the acquisition date.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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