Consolidate net leverage ratio calculated per terms of the Credit Agreement.

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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Data Type:	num:percentItemType
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Period Type:	duration

- Definition

Debt Instrument Issue Price Percentage Of Principal Amount

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Length of facility period for line of credit.

+ References

No definition available.

+ Details

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- Definition

Date the line of credit facility renewed, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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Period Type:	instant

- 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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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

+ Details

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Balance Type:	na
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

+ 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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Period Type:	duration

- 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
Balance Type:	na
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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Namespace Prefix:	us-gaap_
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
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-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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

+ Details

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

- Definition

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

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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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- Definition

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

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of current assets classified as other.

+ References

+ Details

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

- Definition

Amount of noncurrent assets classified as other.

+ References

+ Details

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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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Period Type:	instant

- Details

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Debt - Additional Information (Detail) - USD ($)			9 Months Ended
Debt - Additional Information (Detail) - USD ($)	Feb. 29, 2016	Nov. 10, 2011	Sep. 30, 2016	Nov. 02, 2016	Dec. 31, 2015	Aug. 20, 2013
Debt Instrument [Line Items]
Credit facility, interest rate description			The applicable margin for borrowings under the Revolving Credit Facility is, based on the calculation of the applicable consolidated total leverage ratio, between 0.50% to 1.50% with respect to base rate borrowings and between 1.50% and 2.50% with respect to LIBOR based borrowings. Interest is due and payable monthly. The interest rate in effect at September 30, 2016 for the Credit Facility was 3.03%.
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			3.03%
Other current assets			$ 18,304,000		$ 21,637,000
Current portion of long-term debt			90,270,000		89,710,000
Other noncurrent assets			44,166,000		33,658,000
Long-term debt			652,387,000		834,449,000
Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility amount outstanding			64,000,000
Unused borrowings			161,000,000
Credit facilities, maximum borrowing capacity	$ 250,000,000
Current borrowing capacity due letter of credit	225,000,000
Term Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility amount outstanding			389,100,000
Letters of Credit
Debt Instrument [Line Items]
Unused borrowings			25,000,000
Credit facilities, maximum borrowing capacity	$ 25,000,000
Credit facility period	6 months
Credit facility automatically renewal date	Jun. 15, 2016
ASU 2015-03 [Member]
Debt Instrument [Line Items]
Other current assets					(5,600,000)
Current portion of long-term debt					5,600,000
Other noncurrent assets					(8,800,000)
Long-term debt					$ 8,800,000
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
Debt Instrument [Line Items]
Consolidated Net Leverage Ratio			375.00%
Credit Agreement \| Minimum
Debt Instrument [Line Items]
Credit facility, interest rate margin above base rate			0.50%
Credit facility, interest rate margin above LIBOR rate			1.50%
Credit Agreement \| Maximum
Debt Instrument [Line Items]
Credit facility, interest rate margin above base rate			1.50%
Credit facility, interest rate margin above LIBOR rate			2.50%
Credit Agreement \| Revolving Credit Facility
Debt Instrument [Line Items]
Credit facilities, maximum borrowing capacity		$ 250,000,000
Credit facilities, maturity		5 years
Credit Facility maturity date		Aug. 20, 2018
Credit Agreement \| Term Credit Facility [Member]
Debt Instrument [Line Items]
Credit facilities, maximum borrowing capacity		$ 650,000,000
Credit facilities, maturity		5 years
Credit Facility maturity date		Aug. 20, 2018
Credit Agreement \| Subsequent Event
Debt Instrument [Line Items]
Consolidated Net Leverage Ratio				400.00%
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%