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Fair Value of Financial Instruments - Financial Instruments for which Estimates of Fair Value Differ from Carrying Amounts (Parenthetical) (Details) - USD ($) $ in Thousands | Sep. 30, 2018 | Dec. 31, 2017
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Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |
Deferred financing costs, net | $ 9,928 |
Unsecured Notes Payable [Member] |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |
Deferred financing costs, net | 9,483 | $ 10,575
Unsecured Notes Payable [Member] | Carrying Amount [Member] |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |
Deferred financing costs, net | 8,200 | 8,900
Variable Rate Debt [Member] | Carrying Amount [Member] |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |
Deferred financing costs, net | 1,400 | 1,300
Mortgages Notes Payable [Member] | Carrying Amount [Member] |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |
Deferred financing costs, net | $ 400 | $ 600

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- Definition Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399 + 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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