Count of restricted shares, settle in common shares

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- Definition

Deferred Compensation Arrangement with Individual, Distributions Period, Months

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No definition available.

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- Definition

Deferred Compensation Arrangement With Individual Employer Contribution Percentage

+ References

No definition available.

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- Definition

Deferred Compensation Arrangement with Individual, Interest Rate

+ References

No definition available.

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- Definition

The minimum number of share units awarded to each director under the deferred compensation arrangement.

+ References

No definition available.

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award Share Option Period

+ References

No definition available.

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- Definition

Unamortized Expenses

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No definition available.

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- Definition

The compensation expense recognized during the period pertaining to the deferred compensation arrangement.

+ References

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

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 12

-Paragraph 6, 7

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64, 65

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 710

-SubTopic 10

-Section 30

-Paragraph 1

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- Definition

Description of the deferred compensation arrangement, including fixed amounts and determinable awards, or the method for determining payments and awards, the timing of such payments and awards, and any requisite service or performance criteria, as of the balance sheet date.

+ References

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

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-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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-Paragraph 1

-Subparagraph (a)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64, 65

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-Name Accounting Standards Codification

-Topic 710

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- Definition

Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, 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 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.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)(ii)

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- Definition

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

+ 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 (i)

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-Name Statement of Financial Accounting Standard (FAS)

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The discount rate from market value on offering date that participants pay for shares.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph a

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

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- Definition

Description of pertinent provisions of equity-based compensation awards that have actual or potential impact upon the company's financial statements.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph a

-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.

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-Publisher FASB

-Name Accounting Standards Codification

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Share-Based Compensation (Narrative) (Detail) (USD $) In Millions, except Share data, unless otherwise specified	6 Months Ended	9 Months Ended
	Jun. 30, 2012	Sep. 30, 2012	Sep. 30, 2011	Nov. 30, 2007
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, terms of award	Share options and SARs will count as one share for the purposes of the limits under the 2007 Plan; restricted shares, restricted share units, performance units, performance shares or other share-based incentive awards that settle in common shares will count as 2.75 shares for purpose of the limits under the 2007 Plan.
Deferred compensation arrangement with individual, employer contribution percentage		75.00%
Deferred compensation arrangement with individual, description		Under the Directors Plan, non-employee directors can elect each year to defer payment of 50% or 100% of their cash compensation payable during the next calendar year.
Deferred compensation arrangement with individual, distributions period, months		6
Deferred compensation arrangement with individual, shares authorized for issuance		1,650
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of share options (in years)		P7Y
Share-based compensation arrangement by share-based payment award, discount from market price		100.00%
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, discount from market price		50.00%
Restricted Share Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, compensation expense		$ 1.4	$ 1.1
Employee service share-based compensation, unrecognized compensation costs on nonvested awards		6.0
Restricted Share Units [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting period, maximum, years		4 years
Restricted Share Units [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting period, maximum, years		2 years
Stock-Settled SARs Activity
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, compensation expense		1.7	1.0
Employee service share-based compensation, unrecognized compensation costs on nonvested awards		4.7
Stock-Settled SARs Activity \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting period, maximum, years		4 years
Stock-Settled SARs Activity \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting period, maximum, years		1 year
Cash-Settled SARs Activity [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee service share-based compensation, unrecognized compensation costs on nonvested awards		6.9
Deferred compensation arrangement with individual, compensation expense		3.6	1.3
Cash-Settled SARs Activity [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting period, maximum, years		4 years
Cash-Settled SARs Activity [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting period, maximum, years		1 year
2007 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares authorized				4,500,000
Count of restricted shares, settle in common shares	2.75
Share-based compensation arrangement by share-based payment award, compensation expense		0.5	0.9
Unamortized expense		0.1
Deferred compensation arrangement with individual, interest rate		2 percent above the prime rate
2007 Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting period, maximum, years		5 years	5 years
2007 Plan [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting period, maximum, years		1 year
Amended Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares authorized		6,250,000
Deferred Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred compensation arrangement with individual, compensation expense		$ 0.9	$ 0.4