Description of an amendment to the credit facility.

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Debt Instrument Interest Additional Interest Above Federal Fund Rate

+ References

No definition available.

+ Details

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- Definition

Debt Instrument Interest Additional Interest Above One Month LIBOR Rate

+ References

No definition available.

+ Details

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- Definition

Debt Instrument Issue Price Percentage Of Principal Amount

+ References

No definition available.

+ Details

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- Definition

Percentage of capital stock pledged as collateral under the Company's Credit Agreement.

+ References

No definition available.

+ Details

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- Definition

Maximum amount of charge amendment allows to be excluded from credit facility metric.

+ 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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Period Type:	duration

- Definition

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

+ References

+ Details

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Period Type:	instant

- Definition

Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

+ 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.

+ References

No definition available.

+ Details

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- 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.

+ Details

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Data Type:	xbrli:durationItemType
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Period Type:	duration

- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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.

+ 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Period Type:	instant

- Definition

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

+ References

+ Details

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Balance Type:	na
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- Definition

The effective interest rate at the end of the reporting period.

+ References

+ Details

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Data Type:	num:percentItemType
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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from amounts received from issuance of long-term debt that is wholly or partially secured by collateral. Excludes proceeds from tax exempt secured debt.

+ References

+ Details

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- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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Balance Type:	debit
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- Definition

Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

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Debt - Additional Information (Detail) - USD ($)			9 Months Ended
Debt - Additional Information (Detail) - USD ($)	Jun. 27, 2017	Feb. 24, 2017	Sep. 30, 2017	Sep. 30, 2016	Jun. 15, 2017	Oct. 26, 2016	Feb. 29, 2016	Aug. 20, 2013
Debt Instrument [Line Items]
Proceeds from revolving credit facility			$ 42,000,000	$ 52,000,000
Proceeds from term portion of credit agreement			$ 415,000,000	$ 0
Credit facility, interest rate description			The applicable margin for borrowings under the Credit Facility is, based on the calculation of the applicable consolidated total leverage ratio, between 0.25% to 1.25% with respect to base rate borrowings and between 1.25% and 2.25% with respect to LIBOR rate borrowings. Interest is due and payable monthly. The interest rate in effect at September 30, 2017 for the Credit Facility was 2.99%.
Credit facility, interest rate margin above federal fund rate			1.00%
Credit facility, interest rate margin above one-month LIBOR rate			1.00%
Credit facility, borrowing rate			2.99%
Credit Facility maturity date			Feb. 24, 2022
Description of credit agreement amendment terms	The amendment revised the definition of “Consolidated EBITDA” to exclude the expense from the BHMI judgment and related fees, expenses, and interest thereto, up to $50 million from the calculation in the period recorded		The amendment revised the definition of “Consolidated EBITDA” to exclude the expense from the BHMI judgment and related fees, expenses, and interest thereto, up to $50 million from the calculation in the period recorded
Maximum [Member]
Debt Instrument [Line Items]
BHMI judgment and related fees, expenses, and interest excluded from Consolidated EBITDA definition	$ 50,000,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility amount outstanding			$ 4,000,000
Unused and available borrowings			496,000,000
Term Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility amount outstanding			399,400,000
Letters of Credit [Member]
Debt Instrument [Line Items]
Credit facilities, maximum borrowing capacity					$ 5,000,000	$ 7,500,000	$ 25,000,000
Senior Notes [Member]
Debt Instrument [Line Items]
Senior notes amount outstanding			$ 300,000,000					$ 300,000,000
Issue price percentage of senior notes of the principal amount								100.00%
Percentage of interest rate on notes								6.375%
Maturity date of senior notes			Aug. 15, 2020
Credit Agreement [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Credit facility, interest rate margin above base rate			0.25%
Credit facility, interest rate margin above LIBOR rate			1.25%
Credit Agreement [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Credit facility, interest rate margin above base rate			1.25%
Credit facility, interest rate margin above LIBOR rate			2.25%
Credit Agreement [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facilities, maximum borrowing capacity		$ 500,000,000
Credit facilities, maturity		5 years
Proceeds from revolving credit facility		$ 12,000,000
Credit Agreement [Member] \| Term Credit Facility [Member]
Debt Instrument [Line Items]
Credit facilities, maximum borrowing capacity		$ 415,000,000
Credit facilities, maturity		5 years
Proceeds from term portion of credit agreement		$ 415,000,000
Parent Company and Domestic Subsidiaries [Member]
Debt Instrument [Line Items]
Percentage of capital stock pledged as collateral			100.00%
Foreign Subsidiaries [Member]
Debt Instrument [Line Items]
Percentage of capital stock pledged as collateral			65.00%