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Contractual Life Of Options

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Percentage of performance goal to be achieved for target number of shares to be vest.

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Share based compensation arrangement by share based payment target number of performance based restricted stock unit awards to be earned.

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Term Of Non-Employee Director Stock Option Plan

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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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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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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

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The total cash inflow associated with the amount received from holders to acquire the entity's shares under incentive and share awards, including stock option exercises. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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Description of the period of time over 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, which may be expressed in a variety of ways (for example, in years, month and year).

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Equity-based compensation cost during the period with respect to the award, which will be recognized in income (as well as the total recognized tax benefit) or capitalized as part of the cost of an asset.

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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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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 weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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The number of shares newly issued during the reporting period under the plan.

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Stock-Based Compensation (Narrative) (Details) (USD $)	3 Months Ended		9 Months Ended
Stock-Based Compensation (Narrative) (Details) (USD $)	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-employee director stock option plan, term in years			10
Additional shares available for issuance	4,400,000		4,400,000
Income tax benefit recognized in the income statement for stock-based awards	$ 700,000	$ 600,000	$ 1,500,000	$ 1,500,000
Compensation cost	1,500,000	1,200,000	4,100,000	4,400,000
Percentage of performance goal to be achieved for target number of shares to be vest			100.00%
Targeted number of performance based restricted stock unit awards			100,000
Options issued			399,000	61,000
Closing stock price			13.01
Employee Awards [Member] \| Restricted Stock Units And Phantom Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period, years			four
Employee Awards [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period, years			four
Non-Employee Awards [Member] \| Restricted Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period, years			one
Restricted Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	4,800,000		4,800,000
Unrecognized compensation, years			2.7
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual life of options			10
Unrecognized compensation cost	5,400,000		5,400,000
Unrecognized compensation, years			1.4
Weighted-average grant date fair value, per option			$ 8.14
Proceeds from stock option exercise			1,600,000	1,700,000
Realized an excess tax benefit			400,000	1,300,000
Intrinsic value			900,000	900,000
Restricted Stock Units And Phantom Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	1,600,000		1,600,000
Unrecognized compensation, years			2.2
Performance Based Restricted Stock Unit [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 1,500,000		$ 1,500,000
Unrecognized compensation, years			3.4