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Debt - Mortgage Notes Payable - Additional Information (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
Debt Instrument [Line Items] |  |
Mortgage notes payable | $ 2,385,470 | $ 3,618,722
Debt instrument, maturity date | Jan. 10, 2022 |
Weighted average interest rate | 4.25% | 4.35%
Historical cost, net of accumulated depreciation, of encumbered properties | $ 3,200,000 | $ 4,400,000
ERPOP [Member] |  |
Debt Instrument [Line Items] |  |
Mortgage notes payable | 2,385,470 | 3,618,722
Mortgages [Member] |  |
Debt Instrument [Line Items] |  |
Mortgage notes payable | $ 6,600 |
Repayments of long-term debt |  | $ 10,700
Debt instrument, maturity date | May 28, 2061 | May 28, 2061
Write off of deferred debt issuance cost | $ 3,000 | $ 300
Write off unamortized (premium) discount | $ 16,300 | $ (700)
Weighted average interest rate | 4.15% | 4.33%
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% | 6.90%
Conventional Mortgage Loan [Member] |  |
Debt Instrument [Line Items] |  |
Repayments of long-term debt | $ 43,700 | $ 193,400
Debt instrument, maturity year | 2018 |
Prepayment penalty charges |  | $ 1,500
Debt instrument maturity year, start |  | 2017
Debt instrument maturity year, end |  | 2048
Bonds [Member] |  |
Debt Instrument [Line Items] |  |
Repayments of long-term debt | $ 254,200 |
Debt instrument maturity year, start | 2028 |
Debt instrument maturity year, end | 2042 |
New Floating Rate Tax Exempt Mortgage Bond [Member] | ERPOP [Member] |  |
Debt Instrument [Line Items] |  |
Debt instrument, maturity date | Apr. 01, 2042 |
Proceeds from issuance of long-term debt | $ 96,900 |
Credit enhanced debt [Member] |  |
Debt Instrument [Line Items] |  |
Mortgage notes payable | 440,700 | $ 598,600
Fannie Mae Pool 3 [Member] | Mortgages [Member] |  |
Debt Instrument [Line Items] |  |
Repayments of long-term debt | $ 550,000 | $ 300,000
Debt instrument, interest rate, stated percentage | 6.08% | 5.987%
Debt instrument, maturity year | 2020 | 2019
Prepayment penalty charges | $ 22,100 | $ 10,800
Freddie Mac Loan Pool [Member] | Mortgages [Member] |  |
Debt Instrument [Line Items] |  |
Repayments of long-term debt | $ 500,000 |
Debt instrument, interest rate, stated percentage | 5.19% |
Debt instrument, maturity date | Oct. 01, 2019 |

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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 Contractual interest rate for funds borrowed, under the debt agreement. + 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 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + 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://fasb.org/us-gaap/role/ref/legacyRef -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 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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 3: 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(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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