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Investments in Partially Owned Entities - Other - Additional Information (Details) - USD ($) | Mar. 31, 2018 | Dec. 31, 2017
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Variable Interest Entity [Line Items] |  |
Investments in unconsolidated entities | $ 59,091,000 | $ 58,254,000
Unconsolidated Non-VIE |  |
Variable Interest Entity [Line Items] |  |
Investments in unconsolidated entities | 0 |
Unconsolidated Non-VIE | Residual JV [Member] |  |
Variable Interest Entity [Line Items] |  |
Investments in unconsolidated entities | $ 800,000 |
Joint venture ownership percentage owned by company | 60.00% |
Joint venture partner ownership percentage | 40.00% |
Unconsolidated Non-VIE | Legacy JV [Member] |  |
Variable Interest Entity [Line Items] |  |
Joint venture ownership percentage owned by company | 60.00% |
Joint venture partner ownership percentage | 40.00% |
Liquidation Value Preferred Interests | $ 37,300,000 |
Private Equity Fund | Capital Commitment |  |
Variable Interest Entity [Line Items] |  |
Investments in unconsolidated entities | 4,100,000 |
Private Equity Fund | Maximum [Member] |  |
Variable Interest Entity [Line Items] |  |
Investments in unconsolidated entities | $ 5,000,000 |

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- Definition Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership. + 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 + Details
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