Debt Instrument, Maturity Extension Period

No definition available.

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- Definition

Debt Instrument, Maximum Maturity Extension Period

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Number of Maturity Extension Periods

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-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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Period Type:	instant

- 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
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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

Amount of unamortized debt discount (premium) and debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
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Balance Type:	debit
Period Type:	instant

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

+ Details

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
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-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Section S99
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Debt (Schedule of Debt) (Details)	9 Months Ended	12 Months Ended
Debt (Schedule of Debt) (Details)	Sep. 30, 2020 USD ($) extension	Dec. 31, 2019 USD ($)	Aug. 31, 2020 USD ($)
Debt Instrument [Line Items]
Weighted average rate (percent)	3.03%
Amount outstanding	$ 1,616,835,000	$ 1,481,404,000
$250 Million Unsecured 2018 Term Loan \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate (percent)	0.95%	1.60%
Secured Debt
Debt Instrument [Line Items]
Weighted average rate (percent)	5.55%
Amount outstanding	$ 28,424,000	$ 189,030,000
Net premium (discounts) and unamortized debt issuance costs	448,000	343,000
Secured Debt \| $35 Million Fixed-Rate Loan
Debt Instrument [Line Items]
Face amount of debt instrument	$ 35,000,000	35,000,000
Stated rate (percent)	5.55%
Effective interest rate (percent)	3.75%
Amount outstanding	$ 27,976,000	28,687,000
Secured Debt \| $160 Million Fixed Rate Loan
Debt Instrument [Line Items]
Face amount of debt instrument	$ 160,000,000
Stated rate (percent)	3.48%
Effective interest rate (percent)	3.58%
Amount outstanding	$ 0	160,000,000
Unsecured Debt
Debt Instrument [Line Items]
Weighted average rate (percent)	2.99%
Amount outstanding	$ 1,588,411,000	1,292,374,000
Net premium (discounts) and unamortized debt issuance costs	(11,589,000)	(7,626,000)
Unsecured Debt \| Amended and Restated $300 Million Unsecured 2011 Term Loan
Debt Instrument [Line Items]
Face amount of debt instrument	$ 300,000,000
Effective interest rate (percent)	1.16%
Amount outstanding	$ 300,000,000	300,000,000
Unsecured Debt \| Amended and Restated $300 Million Unsecured 2011 Term Loan \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate (percent)	1.00%
Unsecured Debt \| $500 Million Unsecured 2018 Line of Credit
Debt Instrument [Line Items]
Face amount of debt instrument	$ 500,000,000
Maximum extension period (in years)	1 year
Number of extension periods \| extension	2
Extension period (in months)	6 months
Unsecured Debt \| $500 Million Unsecured 2018 Line of Credit \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate (percent)	0.90%
Unsecured Debt \| $500 Million Unsecured 2018 Line of Credit \| Line of Credit
Debt Instrument [Line Items]
Effective interest rate (percent)	0.00%
Amount outstanding	$ 0	0
Unsecured Debt \| $350 Million Unsecured Senior Notes
Debt Instrument [Line Items]
Face amount of debt instrument	$ 350,000,000
Stated rate (percent)	3.40%
Effective interest rate (percent)	3.43%
Amount outstanding	$ 350,000,000	350,000,000
Unsecured Debt \| $400 Million Unsecured Senior Notes
Debt Instrument [Line Items]
Face amount of debt instrument	$ 400,000,000
Stated rate (percent)	4.45%
Effective interest rate (percent)	4.10%
Amount outstanding	$ 400,000,000	400,000,000
Unsecured Debt \| $250 Million Unsecured 2018 Term Loan
Debt Instrument [Line Items]
Face amount of debt instrument	$ 250,000,000
Effective interest rate (percent)	2.08%
Amount outstanding	$ 250,000,000	250,000,000
Interest rate on derivative instrument	3.56%
Unsecured Debt \| $250 Million Unsecured 2018 Term Loan \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate (percent)	0.95%
Unsecured Debt \| $300 Million 2020 Senior Notes
Debt Instrument [Line Items]
Face amount of debt instrument	$ 300,000,000		$ 300,000,000
Stated rate (percent)			3.15%
Effective interest rate (percent)	3.90%		3.24%
Amount outstanding	$ 300,000,000	$ 0
Interest rate swaps \| $250 Million Unsecured 2018 Term Loan
Debt Instrument [Line Items]
Notional amount of interest rate swap agreements	$ 100,000,000