Number of active stock option plans.

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Number of active stock option plans for employees.

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- Definition

Number of active stock option plans for key executives.

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- Definition

Number of active stock option plans for non-employee directors.

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- Definition

Share based compensation arrangement by share based payment award expiration period.

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Share based compensation arrangement by share based payment award options exercisable number performance conditions attached.

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- Definition

Share-based compensation shares authorized under stock equivalent units exercise price range number of exercisable options.

+ 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

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-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 64

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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-Name Regulation S-X (SX)

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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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.

+ References

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- Definition

Aggregate unrecognized cost of option awards made to employees under a stock option plan or plans, that have yet to vest.

+ References

No definition available.

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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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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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The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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Stockholders' Equity and Stock-Based Compensation Plans (Details Textual) (USD $) In Millions, except Share data, unless otherwise specified			3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2013 Stock Options [Member] Stock_Plan Executives Directors	Mar. 31, 2012 Stock Options [Member]	Mar. 31, 2013 Phantom Share Units PSUs [Member]	Mar. 31, 2012 Phantom Share Units PSUs [Member]	Mar. 31, 2013 Minimum [Member] Stock Options [Member]	Mar. 31, 2013 Minimum [Member] Phantom Share Units PSUs [Member]	Mar. 31, 2013 Maximum [Member] Stock Options [Member]	Mar. 31, 2013 Maximum [Member] Phantom Share Units PSUs [Member]
Stockholders' Equity and Stock-Based Compensation Plans (Textual) [Abstract]
Number of active stock option plans			5
Number of active stock option plans for employees			2
Number of active stock option plans for non-employee directors			1
Number of active stock option plans for key executives			1
Range of stock vesting period							24 months	11 months	6 years	4 years
Expiration term for stock granted			10 years		10 years
Aggregate number of shares of common stock reserved for issuance which can be granted			2,640,000
Number exercisable and fully vested			193,668
Fully vested stock options with performance conditions attached			100,664		150,308
Total compensation cost of SEUs			$ 0.7	$ 0.8	$ 3.7	$ 1.9
Total compensation cost related to non-vested stock options not yet recognized			3.2
Expected compensation cost recognized over the weighted average period			2 years 26 days		1 year 5 months 9 days
Total intrinsic value of options exercised			$ 1.9	$ 0.1	$ 1.2	$ 0.5
Number of exercisable SEUs					185,451
Stockholders' Equity and Stock-Based Compensation Plans (Additional Textual) [Abstract]
Common stock, shares authorized	40,000,000	40,000,000
Number of shares issued	29,554,500	29,554,500
Treasury stock, shares	6,054,840	6,222,076