The value of share options (or share units) forfeited during the period.

No definition available.

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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

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

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-Publisher FASB

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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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.

+ References

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- Definition

The number of grants made 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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

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-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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- Definition

The liabilities paid during the accounting period for equity-based compensation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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-Paragraph 2

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-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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- Definition

The total fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

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

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Share-Based Compensation (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended			0 Months Ended	1 Months Ended		0 Months Ended	12 Months Ended				1 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Feb. 15, 2013 Performance Unit Plan [Member] Performance Units [Member]	Feb. 17, 2012 Performance Unit Plan [Member] Performance Units [Member]	Jan. 21, 2011 Performance Unit Plan [Member] Performance Units [Member]	Jan. 15, 2010 Performance Unit Plan [Member] Performance Units [Member]	Dec. 31, 2013 Performance Unit Plan [Member] Performance Units [Member]	Dec. 31, 2012 Performance Unit Plan [Member] Performance Units [Member]	Dec. 31, 2011 Performance Unit Plan [Member] Performance Units [Member]	Jan. 31, 2013 Performance Unit Plan [Member] Performance Units [Member]	Feb. 21, 2014 Performance Unit Plan [Member] Performance Units [Member] Subsequent Event [Member]	Jan. 31, 2014 Director Incentive Agreement [Member] Performance Units [Member] Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period								5 years					3 years
Awards granted (in units)				22,884	25,040	23,483	25,965					21,991	4,683
Compensation expense	$ 1.5	$ 1.4	$ 1.4
Cash payments distributed related to awards previously granted and now payable											1.0
Awards forfeited during period								0	0	0
Outstanding awards vested during period								$ 4.5