Fair Value of Derivative and Financial Instruments - Additional Information (Details)	3 Months Ended
Mar. 31, 2019 USD ($) DerivativeInstrument	Mar. 31, 2018 USD ($) DerivativeInstrument
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative financial instruments cap weighted average rate	5.81%
Impairment charges related to real estate assets	$ 0	$ 0
Designated as hedging instrument
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Gain (loss) ineffectiveness to derivatives designated as cash flow hedges	0	$ 0
Interest Rate Swap \| One-month LIBOR
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Combined notional amount	$ 650,000,000
Interest rate description	floating interest rate (one-month LIBOR)
Weighted average fixed rate	1.3388%
Interest rate caps
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Combined notional amount	$ 310,000,000
Interest rate description	The interest rate cap agreements the Company has entered into effectively cap one-month LIBOR on $310.0 million of the Company’s floating rate mortgage indebtedness at a weighted average rate of 5.81%.
Interest rate caps \| Not designated as hedging instrument
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Interest rate caps \| DerivativeInstrument	13	11
Derivative notional amount	$ 310,028,000	$ 177,300,000
Minimum \| Interest Rate Swap
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Interest rate term range	4 years
Minimum \| Interest rate caps \| One-month LIBOR
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Interest rate term range	3 years
Maximum \| Interest Rate Swap
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Interest rate term range	5 years
Maximum \| Interest rate caps \| One-month LIBOR
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Interest rate term range	4 years

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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Term of the credit risk derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-SubTopic 10
-Section 50
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Identification of the lender and information about a contractual promise to repay a short-term or long-term obligation, which includes borrowings under lines of credit, notes payable, commercial paper, bonds payable, debentures, and other contractual obligations for payment. This may include rationale for entering into the arrangement, significant terms of the arrangement, which may include amount, repayment terms, priority, collateral required, debt covenants, borrowing capacity, call features, participation rights, conversion provisions, sinking-fund requirements, voting rights, basis for conversion if convertible and remarketing provisions. The description may be provided for individual debt instruments, rational groupings of debt instruments, or by debt in total.

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- Definition

Average cap rate on a group of interest rate derivatives, such as interest rate caps or collars. If market rates exceed the cap rate, a payment or receipt is triggered on the contract.

+ References

No definition available.

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Average fixed interest rate related to the group of interest rate derivatives.

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No definition available.

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- Definition

Nominal or face amount used to calculate payments on the derivative liability.

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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

The net gain (loss) recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

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The charge against earnings in the period to reduce the carrying amount of real property to fair value.

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Number of interest rate derivative instruments held by the entity at the reporting date.

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