Shareholders' Equity (Narrative) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 41,397		$ 41,397
Total intrinsic value of options exercised			4,327
Aggregate intrinsic value of options exercisable	26,977		26,977
Market value of common stock	$ 19.89		$ 19.89
Weighted average exercise price per share	$ 17.37		$ 17.37
Total options that were outstanding	25,564,000		25,564,000
Total options that were exercisable	10,712,000		10,712,000
Shares purchased and retired			4,098,000
Company purchased, cost			79,879
Remaining stock repurchase authorization amount	116,397		116,397
Common Stock, Dividends, Per Share, Declared	$ 0.15	$ 0.12	$ 0.15	$ 0.12
Dividends, Cash			$ 26,117	$ 22,041
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		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%

Market value of common stock.

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Remaining stock repurchase authorization amount

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

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Vesting Rate Higher Specified Diluted Earnings Per Share Targets are Achieved

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No definition available.

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Vesting Rate When Specified Diluted Earnings Per Share Targets are Achieved

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Aggregate dividends declared during the period for each share of common stock outstanding.

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-Publisher SEC

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Equity impact of cash dividends declared by an entity during the period for all classes of stock (common, preferred, etc.). This element includes paid and unpaid dividends declared during the period.

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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 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 dollar difference between fair values of the underlying shares reserved for issuance and exercise prices of vested portions of options outstanding and currently exercisable under the option plan as of the balance sheet date.

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

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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.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

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