Shareholders' Equity (Narrative) (Details) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 62,232
Total intrinsic value of options exercised	9,601
Aggregate intrinsic value of options exercisable	$ 170,509
Market value of Company's common stock (in USD per share) \| $ / shares	$ 52.25
Weighted average exercise price per share (in USD per share) \| $ / shares	$ 33.36
Total options outstanding (in shares) \| shares	15,347
Total options exercisable (in shares) \| shares	9,024
Common Stock Buyback
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares purchased and retired (in shares) \| shares	1,725
Company purchased, cost	$ 88,791
Remaining stock repurchase authorization amount	$ 127,088
2014 Plan \| Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate	50.00%
2014 Plan \| Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate	50.00%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award waiting period	2 years
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award waiting period	4 years

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

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Amount remaining of a stock repurchase plan authorized.

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