Shareholders' Equity (Narrative) (Details) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2017 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 70,634
Total intrinsic value of options exercised	21,407
Aggregate intrinsic value of options exercisable	$ 174,085
Market value of Company's common stock \| $ / shares	$ 50.44
Weighted average exercise price per share \| $ / shares	$ 21.22
Total options outstanding \| shares	17,237
Total options exercisable \| shares	5,958
Common Stock Buyback [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares purchased and retired \| shares	1,099
Company purchased, cost	$ 55,441
Remaining stock repurchase authorization amount	$ 163,311
2014 Plan [Member] \| Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate	50.00%
2014 Plan [Member] \| Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate	50.00%

Unrecognized cost of unvested share-based compensation awards.

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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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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Number of options outstanding, including both vested and non-vested options.

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

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Percentage of vesting of share-based compensation awards.

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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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Amount remaining of a stock repurchase plan authorized.

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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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