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Share-Based Payments (Weighted-Average Fair Value of Options and Stock Per Share) (Details) - $ / shares | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Restricted Stock Units (RSUs) [Member] |  |  |
Stock, weighted average grant date fair value | $ 99.55 | $ 76.09 | $ 64.03
Employee Stock Purchase Plan [Member] |  |  |
Options, weighted average grant date fair value | 6.67 | 4.43 | 4.69
Discount of grant date market value | 13.91 | 12.61 | 10.98
Total ESPP | 20.58 | 17.04 | 15.67
Agent Stock Purchase Plan [Member] |  |  |
Stock, weighted average grant date fair value | $ 9.99 | $ 8.28 | $ 7.57

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- Definition The weighted average fair value discount at grant date, for employee stock purchase plan shares issued during the period. + References No definition available. + Details
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- Definition The total weighted average fair value at grant date for employee stock purchase plan shares issued during the period. + References No definition available. + Details
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(01) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
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- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (d)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
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