Debt - Mortgage Notes Payable - Additional Information (Details) - USD ($)	6 Months Ended
Jun. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Mortgage notes payable	$ 2,599,013,000	$ 2,385,470,000
Debt instrument, maturity date	Jan. 10, 2022
Mortgages [Member]
Debt Instrument [Line Items]
Mortgage notes payable	$ 3,100,000
Debt instrument, maturity date	May 28, 2061
Write off of deferred debt issuance cost	$ 1,500,000
Write off unamortized (premium) discount	$ 15,100,000
Weighted average interest rate	4.01%
Mortgages [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	0.10%
Mortgages [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	5.78%
Variable Rate Construction Mortgage [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Jun. 25, 2022
Variable rate of construction mortgage debt	$ 7,500,000
Total commitment amount	67,600,000
Bonds [Member]
Debt Instrument [Line Items]
Repayments of long-term debt	$ 95,500,000
Debt Instrument Maturity year	2036
Credit enhanced debt [Member]
Debt Instrument [Line Items]
Mortgage notes payable	$ 345,000,000.0
Fannie Mae Pool 3 [Member] \| Mortgages [Member]
Debt Instrument [Line Items]
Proceeds from issuance of long-term debt	$ 288,100
Debt instrument, maturity date	Mar. 01, 2029
Debt instrument, interest rate, stated percentage	3.94%

Debt instrument maturity year.

No definition available.

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- Definition

Amount of write off of unamortized discount premium net.

+ References

No definition available.

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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

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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.

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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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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- Definition

Amount of the fee for available but unused credit capacity under the credit facility.

+ References

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- Definition

The portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

+ References

No definition available.

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- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

+ References

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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.

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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.

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- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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