Fair Value Measurements (Details) - Mortgages and Loans Payable - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Fair Value Inputs, Liabilities, Quantitative Information
Recorded value	$ 1,232,190	$ 1,065,180
Deferred financing costs	7,411	9,024
Fair Value, Level 3 Inputs
Fair Value Inputs, Liabilities, Quantitative Information
Fair value	$ 1,226,748	$ 1,056,990

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.

No definition available.

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- Definition

Fair value portion of contractual obligation to pay money on demand or on fixed or determinable dates.

+ References

No definition available.

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- Definition

Amount of long-term debt and capital lease obligations including current maturities.

+ References

No definition available.

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ 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 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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