Accumulated service period for voluntary termination.

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- Definition

Age limit of voluntary termination of employment.

+ References

No definition available.

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- Definition

Maximum percentage of the participants base units.

+ References

No definition available.

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- Definition

Number of executives with employment agreements

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Term, Maximum

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Term, Minimum

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Cliff Vesting, Minimum

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Recognized compensation expense awards nominal amounts capitalized

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, shares are delivered

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No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award VestingPeriod1

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- Definition

Share Based Compensation Arrangement By Share Based Payment Stock Options Nonvested Number.

+ References

No definition available.

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- Definition

Voluntary termination of employment terms.

+ References

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

-Paragraph 2

-Subparagraph (h)(1)(i)

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

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-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.

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-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

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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

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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

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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 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

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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

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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).

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- Definition

The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(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 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

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

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(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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Share Based and Deferred Compensation Share Based and Deferred Compensation (Details Textuals) (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended			3 Months Ended					3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012	Mar. 31, 2013 Stock Option [Member]	Mar. 31, 2012 Stock Option [Member]	Mar. 31, 2013 Restricted Stock [Member]	Mar. 31, 2012 Restricted Stock [Member]	Dec. 31, 2012 Restricted Stock [Member]	Mar. 31, 2013 Restricted Performance Share Units Plan [Member] Age Employees	Mar. 31, 2012 Restricted Performance Share Units Plan [Member]	Mar. 31, 2011 Restricted Performance Share Units Plan [Member]	Apr. 02, 2009 Restricted Performance Share Units Plan [Member]	Mar. 31, 2013 Executive Officer [Member] Restricted Stock [Member] Employees	Feb. 25, 2013 Executive Officer [Member] Restricted Stock [Member]	Feb. 25, 2013 Executive Officer [Member] Restricted Performance Share Units Plan [Member]	Mar. 01, 2012 Executive Officer [Member] Restricted Performance Share Units Plan [Member]	Mar. 02, 2011 Executive Officer [Member] Restricted Performance Share Units Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Voluntary Termination Of Employment Terms						after reaching age 57 and accumulating at least 15 years of service with the Company			after reaching age 57 and accumulating at least 15 years of service with the Company
Accumulated Service Period For Voluntary Termination						15 years			15 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Term, Minimum	1 year					3 Years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Term, Maximum	10 years					7 Years
Share-based Compensation Arrangement by Share-based Payment Award, Cliff Vesting After Grant Date, Minimum						3 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period									3 years
Maximum Percentage Of Participants Base Units									200.00%
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized														157,208	231,093	242,122	113,256
Number of executives with employment agreements									2				2
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Total Fair Value									$ 4.1	$ 4.2	$ 2.0
Age Limit Of Voluntary Termination Of Employment									57
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number						719,677		597,708
Share Based Compensation Arrangement By Share Based Payment Award VestingPeriod1						three to seven years from the initial grant date
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	3,166,998		3,337,549	3,166,998
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition					0 years 10 months 25 days	1 year 4 months 21 days
Share Based Compensation Arrangement By Share Based Payment Stock Options Nonvested Number				184,430
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized				0.5		3.8
Allocated Share-based Compensation Expense	2.3	1.7				0.9	0.7		1.2	0.6
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount	0.5	0.4		0.3	0.4	0.2			0.3	0.2
Share-based Compensation Arrangement by Share-based Payment Award, shares are delivered												372,102
Share-based Compensation Arrangement by Share-based Payment Award, Recognized compensation expense awards					$ 0.1