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Related Party Transactions and Investments in Non-Consolidated Entities - Investment in Sponsored REITs - Property Sold (Details) | 12 Months Ended
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Dec. 31, 2017 USD ($) entity | Dec. 31, 2016 USD ($) entity
Investment in Sponsored REITs |  |
Number of properties sold | entity | 1 | 2
FSP 1441 Main Street Corp. |  |
Investment in Sponsored REITs |  |
Repayment of principal | $ 9,000,000 |
FSP 385 Interlocken Development, Corp. |  |
Investment in Sponsored REITs |  |
Repayment of principal |  | $ 37,500,000

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- Definition Represents the number of properties owned by sponsored REITs which were sold during the period. + References No definition available. + Details
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- Definition The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations. + References No definition available. + 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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Balance Type: |
Period Type: |