Shareholders' Equity (Narrative) (Details) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2021 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 101,002
Total intrinsic value of options exercised	11,511
Aggregate intrinsic value of options exercisable	$ 131,300
Market value of Company's common stock (in USD per share) \| $ / shares	$ 60.93
Weighted average exercise price per share (in USD per share) \| $ / shares	$ 39.78
Total options outstanding (in shares) \| shares	17,923
Total options exercisable (in shares) \| shares	6,207
Common Stock Buyback
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares purchased and retired (in shares) \| shares	1,152
Company purchased, cost	$ 66,939
Remaining stock repurchase authorization amount	$ 125,888
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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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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 remaining of a stock repurchase plan authorized.

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