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Stock Plans and Share-Based Compensation - Restricted Stock Grant and Vesting Information (Details) - Restricted Stock Units and Awards - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Weighted-average grant date fair value (in dollars per share) | $ 79.30 | $ 69.19 | $ 62.60
Fair value of units vested in fiscal year ending (in millions) | $ 8 | $ 7 | $ 9

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- Definition Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options Weighted Average Grant Date Fair Value + References No definition available. + Details
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Period Type: | instant

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- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. + 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 (d)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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