v2.4.0.8

Financing Debt - Additional Information (Detail) (USD $)	9 Months Ended	1 Months Ended	9 Months Ended				1 Months Ended		1 Months Ended					9 Months Ended
	Sep. 30, 2013	Jan. 30, 2013 Senior Notes	Sep. 30, 2013 Senior Notes	Sep. 30, 2013 Semi Annual Payment, First Payment Senior Notes	Sep. 30, 2013 Semi Annual Payment, Second Payment Senior Notes	Jan. 18, 2013 2013 Credit Agreement	Jan. 18, 2013 2013 Credit Agreement Term Loans Facility	May 23, 2011 2013 Credit Agreement Term Loans Facility	Jan. 18, 2013 2013 Credit Agreement Revolving Credit Facility	Jan. 30, 2013 2013 Credit Agreement Revolving Credit Facility	May 23, 2011 2013 Credit Agreement Revolving Credit Facility	Jan. 18, 2013 2013 Credit Agreement Revolving Credit Facility Minimum	Jan. 18, 2013 2013 Credit Agreement Revolving Credit Facility Letter of Credit	Sep. 30, 2013 Senior Notes Redeemed Prior to February One Twenty Sixteen	Sep. 30, 2013 Senior Notes Redeemed Prior to February One Twenty Eighteen
Debt Instrument [Line Items]
Credit agreement loan, term							5 years		5 years
Credit agreement loan, maximum							$ 300,000,000		$ 800,000,000	$ 700,000,000			$ 150,000,000
Principal remaining outstanding amount												300,000,000
Credit agreement loan, option to increase						100,000,000
Credit agreement outstanding amount								185,000,000			700,000,000
Debt instrument, aggregate principal amount		$ 400,000,000
Debt instrument, interest rate		4.75%
Debt instrument, issuance price as a percentage of principal amount		100.00%
Debt instrument, maturity date			Feb. 01, 2023
Debt instrument, interest payable month and day				--02-01	--08-01
Debt instrument, interest payment commencement date			Aug. 01, 2013
Debt instrument, redemption percentage														35.00%
Debt instrument, redemption price as a percentage of principal amount														104.75%	100.00%
Debt instrument, redemption date	Feb. 01, 2018													Feb. 01, 2016
Debt repurchase price	101.00%

X

- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400

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Balance Type:	credit
Period Type:	instant

X

- Definition

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

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5



Reference 2: 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

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X

- Details

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

X

- Definition

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

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5



Reference 2: 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)(2))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Balance Type:	na
Period Type:	duration

X

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 50

-Paragraph 3

-Subparagraph e

-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

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X

- Definition

Percentage of principal amount of debt redeemed.

+ References

No definition available.

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X

- 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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Balance Type:	na
Period Type:	duration

X

- Definition

Amount borrowed under the credit facility as of the balance sheet date.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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Balance Type:	credit
Period Type:	instant

X

- 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

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



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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X

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ 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



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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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Balance Type:	credit
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X

- Definition

Debt Instrument, First Interest Payment Date

+ References

No definition available.

+ Details

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

X

- Definition

Debt Instrument, Interest Rate Payment, Day and Month

+ References

No definition available.

+ Details

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X

- Definition

Debt Instrument Issuance Price Percent Of Total

+ References

No definition available.

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X

- Definition

Debt Instrument Redemption Date

+ References

No definition available.

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X

- Definition

Debt Instrument Repurchase Price Percentage On Principal Amount Plus Accrued And Unpaid Interest

+ References

No definition available.

+ Details

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X

- Definition

Line of Credit Facility, Optional Maximum Borrowing Capacity

+ References

No definition available.

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