Investments in Unconsolidated Real Estate Ventures - Equity Method Investments (Details) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($) store joint_venture	Dec. 31, 2016 USD ($) store joint_venture	Dec. 31, 2015 USD ($) store joint_venture
Schedule of Equity Method Investments [Line Items]
New unconsolidated joint ventures, number \| joint_venture	4	8	1
Number of operating stores owned \| store	39	8	1
Equity method ownership percentage	25.00%		50.00%
Initial Investment \| $	$ 13,341	$ 26,387	$ 2,885
Minimum
Schedule of Equity Method Investments [Line Items]
Equity method ownership percentage	10.00%	20.00%
Maximum
Schedule of Equity Method Investments [Line Items]
Equity method ownership percentage		50.00%

Equity Method Investment, New Unconsolidated Joint Ventures, Number

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- Definition

Number of Operating Stores Owned

+ References

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- Definition

This element represents the aggregate cost of investments accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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- Definition

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+ References

No definition available.

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