The Bonds that are subject to interest rate cap agreements.

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- Definition

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

+ References

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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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

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-Topic 860
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- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
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- Definition

Amount of increase in the fair value of derivatives recognized in the income statement.

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-Publisher FASB
-Name Accounting Standards Codification
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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

The number of derivative instruments of a particular group held by the entity.

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- Definition

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

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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Derivative Instruments and Hedging Activities (Details)	1 Months Ended	12 Months Ended
Derivative Instruments and Hedging Activities (Details)	Nov. 30, 2016 USD ($)	Dec. 31, 2018 USD ($) instrument	Dec. 31, 2017 USD ($) instrument	Dec. 31, 2016 USD ($) instrument	Oct. 31, 2016 USD ($)
Derivative [Line Items]
Unsecured debt, net		$ 3,799,316,000	$ 3,501,709,000
Total return swap income		8,707,000	10,098,000	$ 11,716,000
Designated as Hedging Instrument [Member]
Derivative [Line Items]
Hedge ineffectiveness related to cash flow hedges		$ 100,000	$ 100,000	$ 300,000
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member]
Derivative [Line Items]
Number of derivative instruments held \| instrument		5	1	4
Average fixed interest rate		2.30%
Derivative, fair value		$ 5,800,000	$ 5,400,000
Aggregate carrying value of the interest rate swap contracts		0	0
Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Total return swap income		8,700,000	$ 10,100,000	$ 11,700,000
Not Designated as Hedging Instrument [Member] \| Interest Rate Cap [Member]
Derivative [Line Items]
Number of derivative instruments held \| instrument			3
Derivative, notional amount		9,900,000	$ 20,700,000
Derivative, fair value		0	0
Not Designated as Hedging Instrument [Member] \| Total Return Swap [Member]
Derivative [Line Items]
Derivative, fair value		$ 0	0
Not Designated as Hedging Instrument [Member] \| Total Return Swap [Callable]
Derivative [Line Items]
Number of derivative instruments held \| instrument		4
Derivative, notional amount		$ 256,024,000
Variable rate term loan [Member]
Derivative [Line Items]
Unsecured debt, net	$ 350,000,000				$ 225,000,000
Debt instrument, term	5 years
Basis spread on rate		0.95%
Variable rate term loan [Member] \| Interest Rate Swap [Member]
Derivative [Line Items]
Unsecured debt, net		$ 350,000,000	$ 350,000,000
Number of derivative instruments held \| instrument		5
Variable rate term loan [Member] \| Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member]
Derivative [Line Items]
Derivative, notional amount		$ 175,000,000
Variable rate mortgage notes payable [Member]
Derivative [Line Items]
Bond subject to interest rate caps		256,000,000
Variable rate mortgage notes payable [Member] \| Total Return Swap [Member]
Derivative [Line Items]
Bond subject to interest rate caps		$ 9,900,000