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Debt - Mortgage Notes Payable - Additional Information (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 USD ($) Property | Dec. 31, 2016 USD ($) Property
Debt Instrument [Line Items] |  |
Mortgage notes payable | $ 3,618,722 | $ 4,119,181
Debt instrument, maturity date | Jan. 10, 2022 |
Historical cost, net of accumulated depreciation, of encumbered properties | $ 4,400,000 | 5,000,000
Noncash or part noncash acquisition, debt assumed |  | $ 43,400
Properties acquired | Property | 4 | 4
Mortgages [Member] |  |
Debt Instrument [Line Items] |  |
Repayments of long-term debt | $ 10,700 | $ 8,500
Write off of deferred debt issuance cost | 300 | 1,600
Write off unamortized (premium) discount | $ 700 | $ 20,700
Debt instrument, maturity date | May 28, 2061 | May 28, 2061
Weighted average interest rate | 4.33% | 4.34%
Properties acquired | Property |  | 1
Mortgages [Member] | Minimum [Member] |  |
Debt Instrument [Line Items] |  |
Debt instrument, interest rate, stated percentage | 0.10% | 0.10%
Mortgages [Member] | Maximum [Member] |  |
Debt Instrument [Line Items] |  |
Debt instrument, interest rate, stated percentage | 6.90% | 7.20%
Conventional Mortgage Loan [Member] |  |
Debt Instrument [Line Items] |  |
Repayments of long-term debt | $ 193,400 | $ 75,900
Prepayment penalty charges | $ 1,500 | 2,200
Debt instrument maturity year, start | 2017 |
Debt instrument maturity year, end | 2048 |
Credit enhanced debt [Member] |  |
Debt Instrument [Line Items] |  |
Mortgage notes payable | $ 598,600 | 601,900
Bonds [Member] |  |
Debt Instrument [Line Items] |  |
Repayments of long-term debt |  | 65,500
Prepayment penalty charges |  | $ 200
Debt instrument maturity year, start |  | 2026
Debt instrument maturity year, end |  | 2037
Mortgage Loan - Floating Rate [Member] |  |
Debt Instrument [Line Items] |  |
Repayments of long-term debt |  | $ 900
Fannie Mae Pool 3 [Member] | Mortgages [Member] |  |
Debt Instrument [Line Items] |  |
Repayments of long-term debt | $ 300,000 | $ 440,800
Debt instrument, interest rate, stated percentage | 5.987% | 6.256%
Debt instrument, maturity year | 2019 | 2017
Prepayment penalty charges | $ 10,800 | $ 29,300

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- Definition Debt instrument maturity year, start. + References No definition available. + Details
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- Definition Represents a total which may include the following: land available-for-development, investments in building and building improvements, developments-in-process, and furniture and fixtures for properties that are encumbered by mortgages. + References No definition available. + Details
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- Definition Amount of write off of unamortized discount premium net. + References No definition available. + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + 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 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + 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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- Definition Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format. + 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 210.5-02.22(a)(2)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition The amount of debt that an Entity assumes in acquiring a business or in consideration for an asset received in a noncash (or part noncash) acquisition. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586 + Details
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- Definition The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585 + Details
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- Definition Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: 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(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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- Definition Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.8) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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