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Shareholders' Equity (Narrative) (Details) $ / shares in Units, shares in Thousands, $ in Thousands | 3 Months Ended
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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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- Definition Unrecognized cost of unvested share-based compensation awards. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iii) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iii) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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