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.

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- Definition

The weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, using a decimal to express in number of years.

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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

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- 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

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(2)(c)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 2

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

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

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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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

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

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- Definition

Net number of share options (or share units) granted during the period.

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- Definition

An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

+ References

+ Details

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- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64

-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

-Subparagraph (g)

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

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- Definition

The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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- Definition

Increase in number of shares available for grant

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- Definition

The amount of accelerated expense on modified stock options awards that would have been recognized over the remaining life of the options had they not been accelerated.

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- Definition

The floor of fair values related to options granted during the period.

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- Definition

The ceiling of fair values related to options granted during the period.

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- Definition

The current amount each share based award for share based compensation counts against the shares available for grant.

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- Definition

The previous amount each share based award for share based compensation counted against the shares available for grant

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- Definition

Represents the Stock Options vest percentage on date of grant.

+ Details

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- Definition

Represents the Stock Options vest percentage for periods after the initial vest.

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- Definition

The contractual life of issued stock options.

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- Definition

Stock Prices on the Dates Of Modification

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Share-Based Compensation (Narrative) (Details) (USD $) In Millions, except Share data, unless otherwise specified	0 Months Ended	9 Months Ended					9 Months Ended				9 Months Ended
	Aug. 15, 2011	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2010 Minimum [Member]	Sep. 30, 2010 Maximum [Member]	Oct. 06, 2011 Prior [Member] 2005 Incentive Plan [Member]	Sep. 30, 2011 2005 Incentive Plan [Member]	Sep. 30, 2010 2005 Incentive Plan [Member]	Oct. 06, 2011 2005 Incentive Plan [Member]	Dec. 31, 2010 2005 Incentive Plan [Member]	Sep. 30, 2011 Stock Options [Member]	Sep. 30, 2011 Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant							1,692,940			2,068,375
Share-based compensation current granted counts												2.1
Share-based compensation previous granted counts												1.17
Additional compensation expense that would have been recognized			$ 0.7
Total shares authorized for issuance						23,000,000			28,500,000
Increase in number of shares available for grant									5,500,000
Total share-based compensation to be recognized on unvested awards		26.1									17.6	8.5
Total share-based compensation to be recognized, weighted average period (Years)											1.40	2.90
Shares granted on purchased option							101,800	489,600
Exercise price of the stock option minimum			$ 7.50				$ 14.55	$ 13.97
Exercise price of the stock option maximum			$ 24.66				$ 20.78	$ 22.22
Stock option expiry term							10
Exercise price of the stock option fair value minimum							$ 7.77	$ 7.43
Exercise price of the stock option fair value maximum							$ 11.62	$ 12.77
Stock options vesting percentage							25.00%
Stock options vesting percentage in future period							25.00%
Additional compensation expense related to modification of option			$ 0.9
Stock prices on the dates of modification				$ 14.70	$ 21.23
Shares of common stock granted	689,100	689,100
Weighted average grant date fair value Non-vested shares, Granted		$ 14.83