Adjusted LIBOR rate

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- Definition

Unsecured Revolving Credit Facility

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No definition available.

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The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD.

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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.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

+ References

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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.

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No definition available.

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- Definition

Amount of the required periodic payments applied to principal.

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- Definition

Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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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.

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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

No definition available.

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- Definition

Carrying value as of the balance sheet date of the portion of long-term notes having the highest claim on the assets of the issuer in case of bankruptcy or liquidation, due within one year or the normal operating cycle, if longer. Senior note holders are paid off in full before any payments are made to debt holders having a lesser priority of repayment.

+ References

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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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Carrying value as of the balance sheet date of uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

+ References

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- Definition

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

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Long-Term Debt - Narrative (Detail) - USD ($)	3 Months Ended			9 Months Ended	12 Months Ended
Long-Term Debt - Narrative (Detail) - USD ($)	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Sep. 30, 2018	Dec. 31, 2017	Mar. 31, 2018	Jun. 28, 2017	Jan. 15, 2015	Sep. 18, 2014	Apr. 17, 2014	Sep. 15, 2011	Feb. 01, 2008	Dec. 22, 2006
Debt Instrument [Line Items]
Document Period End Date				Sep. 30, 2018
Credit facility, outstanding amount		$ 340,000,000		$ 340,000,000	$ 365,000,000
Unsecured revolving credit facility							$ 400,000,000.0			$ 800,000,000.0
Write off of Deferred Debt Issuance Cost		200,000
Debt Issuance Costs, Noncurrent, Net							$ 1,600,000
Debt Instrument, Periodic Payment, Principal		5,000,000.0	$ 5,000,000.0
Proceeds from Issuance of Debt		2,800,000
Unsecured term loans						$ 370,000,000.0
Outstanding debt balance		862,361,000		862,361,000	976,141,000
4.500% senior notes, Series E, quarterly interest payments, balloon due September 2018
Debt Instrument [Line Items]
Current portion of senior notes		0		0	$ 100,000,000			$ 25,000,000.0
Unsecured Senior Notes
Debt Instrument [Line Items]
Debt instrument interest rate stated percentage									4.20%
Debt instrument, face amount									$ 500,000,000.0
Outstanding debt balance		500,000,000.0		$ 500,000,000.0
Term Loan
Debt Instrument [Line Items]
Debt Instrument, Periodic Payment, Principal		67,500,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility, outstanding amount									$ 475,000,000.0
Master Agreement \| Series C
Debt Instrument [Line Items]
Unsecured senior notes outstanding												$ 25,000,000.0	$ 25,000,000.0
Debt instrument interest rate stated percentage													5.66%
Master Agreement \| Series D
Debt Instrument [Line Items]
Debt instrument interest rate stated percentage												5.37%
Master Agreement \| Series E
Debt Instrument [Line Items]
Unsecured senior notes outstanding											$ 100,000,000.0
Payment for Debt Extinguishment or Debt Prepayment Cost		$ 700,000
Debt instrument interest rate stated percentage											4.50%
LIBOR
Debt Instrument [Line Items]
30-day Adjusted LIBOR Rate		2.125%		2.125%
Maximum \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Facility fee				0.25%	0.25%
Maximum \| LIBOR \| Term Loan
Debt Instrument [Line Items]
Debt instrument, variable interest rate				1.75%	1.75%
Maximum \| LIBOR \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt instrument, variable interest rate				1.50%	1.50%
Scenario, Forecast [Member]
Debt Instrument [Line Items]
Debt Instrument, Periodic Payment, Principal	$ 5,000,000.0