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

No definition available.

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Data Type:	xbrli:monetaryItemType
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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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Data Type:	xbrli:stringItemType
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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

Shares Deferred By Recipients.

+ References

No definition available.

+ Details

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- 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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 non-option equity instruments exercised by participants.

+ References

+ Details

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

- Definition

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

+ References

+ Details

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

- Definition

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

+ References

+ Details

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

- Definition

Gross number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP). Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

+ References

No definition available.

+ 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	3 Months Ended	6 Months Ended	0 Months Ended	3 Months Ended	6 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		0 Months Ended	6 Months Ended
	Jun. 18, 2011 Performance Based Grants [Member] 2008 Plan [Member]	Jun. 16, 2012 Performance Based Grants [Member]	Dec. 17, 2008 Stock Appreciation Rights (SARs) [Member]	Mar. 24, 2012 Stock Appreciation Rights (SARs) [Member]	Jun. 16, 2012 Stock Appreciation Rights (SARs) [Member]	Dec. 31, 2011 Stock Appreciation Rights (SARs) [Member]	Jun. 16, 2012 Time Vesting Equity Units [Member]	Jun. 16, 2012 Performance Vesting Unit [Member]	Jun. 16, 2012 Selling, General and Administrative Expenses [Member]	Jun. 18, 2011 Selling, General and Administrative Expenses [Member]	Jun. 16, 2012 Selling, General and Administrative Expenses [Member]	Jun. 18, 2011 Selling, General and Administrative Expenses [Member]	Dec. 31, 2011 2009 Plan [Member] LTIP [Member]	Jun. 16, 2012 2012 Plan [Member] LTIP [Member]
Allocated Share-based Compensation Expense (in Dollars)									$ 0.5	$ 1.4	$ 1.6	$ 2.5
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Exercised	104,111
Stock Issued During Period, Shares, Share-based Compensation, Gross	122,000
Share Based Compensation, Stock Deferred By Recipients During Period, Shares	96,000
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Forfeitures		(21,500)			23,800								90,670
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted		207,400	267,345											207,035
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) (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		(1,400)			243,545
Deferred Tax Asset Write Off (in Dollars) (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)							$ 23.16	$ 29.29