Shareholders' Equity (Narrative) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 45,567
Total intrinsic value of options exercised	13,602
Aggregate intrinsic value of options exercisable	89,066
Share Price	$ 28.85
Weighted average exercise price per share	$ 18.24
Total options that were outstanding	24,087,000
Total options that were exercisable	8,393,000
Shares purchased and retired	1,268,000
Company purchased, cost	36,181
Remaining stock repurchase authorization amount	$ 54,831
2007 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of active equity compensation plans	1
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	20,000,000
Vesting Rate When Specified Diluted Earnings Per Share Targets are Achieved	50.00%
Vesting Rate Higher Specified Diluted Earnings Per Share Targets are Achieved	50.00%

Share based compensation arrangement by share based payment award, number of active plans.

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- Definition

Vesting Rate Higher Specified Diluted Earnings Per Share Targets are Achieved

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Vesting Rate When Specified Diluted Earnings Per Share Targets are Achieved

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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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

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-Paragraph A240

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- Definition

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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-Topic 718

-SubTopic 10

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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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- Definition

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.

+ References

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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.

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- Definition

Price of a single share of a number of saleable stocks of a company.

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- Definition

Number of shares that have been repurchased and retired during the period.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

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-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

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- Definition

The remaining repurchase amount authorized by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

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