Write Off deferred tax asset related to SAR to be offset against additional paid in capital.

No definition available.

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- Definition

The percentage of the number of Performance Units Granted as shares.

+ References

No definition available.

+ Details

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the SARS.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph g(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.F)

-URI http://asc.fasb.org/extlink&oid=6793087&loc=d3e301413-122809

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

+ Details

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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of shares under non-option equity instrument agreements for which rights to exercise lapsed.

+ References

+ Details

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Data Type:	xbrli:sharesItemType
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Period Type:	duration

- Definition

Number of shares under non-option equity instrument agreements that were cancelled as a result of occurrence of a terminating event.

+ References

+ Details

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Period Type:	duration

- Definition

Net number of non-option equity instruments granted to participants.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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Share-Based Compensation (Detail) (USD $) In Millions, except Share data, unless otherwise specified	0 Months Ended	3 Months Ended	9 Months Ended			0 Months Ended	9 Months Ended	4 Months Ended		9 Months Ended
	Dec. 17, 2008 Stock Appreciation Rights (SARs) [Member]	Mar. 24, 2012 Stock Appreciation Rights (SARs) [Member]	Oct. 06, 2012 Stock Appreciation Rights (SARs) [Member]	Oct. 06, 2012 Time Vesting Equity Units[Member]	Oct. 06, 2012 Performance Vesting Units[Member]	Dec. 31, 2011 LTIP [Member] 2009 Plan [Member]	Oct. 06, 2012 LTIP [Member] 2012 Plan [Member]	Oct. 06, 2012 Selling, General and Administrative Expenses [Member]	Oct. 08, 2011 Selling, General and Administrative Expenses [Member]	Oct. 06, 2012 Selling, General and Administrative Expenses [Member]	Oct. 08, 2011 Selling, General and Administrative Expenses [Member]
Allocated Share-based Compensation Expense (in Dollars)								$ 2.9	$ 1.8	$ 1.3	$ 4.3
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Forfeitures			23,800			90,670
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted	267,345						209,693
Percentage Of Number Of Performance Units Granted In Shares							zero to 200%
Share-based Compensation Arrangement by Share-based Payment Award, Other Than Options, Outstanding, Weighted Average Exercise Price (in Dollars per share)	$ 38.44		$ 38.44
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number			267,345
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Expirations			243,545
Deferred Tax Asset Write Off (in Dollars)		$ 0.8
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in Dollars per share)				$ 23.03	$ 29.19