Debt Instruments Maturity Year

No definition available.

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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

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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

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 the required periodic payments applied to interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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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Balance Type:	debit
Period Type:	duration

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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- Definition

Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

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Balance Type:	credit
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- Details

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Long-Term Debt - Long-Term Debt Instrument (Additional Information) (Detail) - USD ($)	3 Months Ended		12 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Sep. 15, 2011
5.660% senior notes, Series C, semi-annual interest payments, balloon due 2016
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			4.50%	4.50%
4.500% senior notes, Series E, quarterly interest payments, balloon due 2018
Debt Instrument [Line Items]
Debt instrument maturity year			2018	2018
4.200% Senior Notes, semi-annual interest payments, balloon due 2024
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage			4.20%	4.20%
Debt instrument maturity year			2024	2024
5-year term loan facility, periodic interest and principal payments, LIBOR plus up to 1.750%, expires June 28, 2022
Debt Instrument [Line Items]
Line of credit facility, expiration period			5 years	5 years
Line of credit facility, expiration date			Jun. 28, 2022	Jun. 28, 2022
5-year term loan facility, periodic interest and principal payments, LIBOR plus up to 1.750%, expires June 28, 2022 \| LIBOR
Debt Instrument [Line Items]
Debt instrument, variable interest rate			1.75%	1.75%
5-year revolving loan facility, periodic interest payments, currently LIBOR plus up to 1.500%, plus commitment fees up to 0.250%, expires June 28, 2022
Debt Instrument [Line Items]
Line of credit facility, expiration period			5 years	5 years
Line of credit facility, commitment fee percentage			0.25%	0.25%
Line of credit facility, expiration date			Jun. 28, 2022	Jun. 28, 2022
5-year revolving loan facility, periodic interest payments, currently LIBOR plus up to 1.500%, plus commitment fees up to 0.250%, expires June 28, 2022 \| LIBOR
Debt Instrument [Line Items]
Debt instrument, variable interest rate			1.50%	1.50%
Maximum
Debt Instrument [Line Items]
Debt instrument, variable interest rate			1.75%
Master Agreement [Member] \| Series E [Member]
Debt Instrument [Line Items]
Debt Instrument, Periodic Payment, Interest		$ 700,000
Payment for Debt Extinguishment or Debt Prepayment Cost	$ 700,000
Debt instrument, interest rate, stated percentage					4.50%