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Stock-Based Compensation Plans - Summary of Transactions of the Company's Stock Option Plans (Detail) - Stock Options Plan [Member] | 9 Months Ended
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Sep. 30, 2021 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Outstanding, Number of Options, Beginning balance | shares | 442,893
Exercised, Number of Options | shares | (56,508)
Forfeited, Number of Options | shares | (19,023)
Outstanding, Number of Options, Ending balance | shares | 459,646
Outstanding, Weighted Average Exercise Price, Beginning balance | $ 32.49
Exercised, Weighted Average Exercise Price | 34.57
Forfeited, Weighted Average Exercise Price | 20.46
Outstanding, Weighted Average Exercise Price, Ending balance | 28.44
Outstanding, Weighted Average Grant-Date Fair Value | 45.31
Exercised, Weighted Average Grant-Date Fair Value | 37.45
Forfeited, Weighted Average Grant-Date Fair Value | 63.56
Outstanding, Weighted Average Grant-Date Fair Value | $ 53.64
Discount [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted, Number of Options | shares | 81,596
Granted, Weighted Average Exercise Price | $ 0.00
Granted, Weighted Average Grant-Date Fair Value | $ 92.37
Market Value [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted, Number of Options | shares | 10,688
Granted, Weighted Average Exercise Price | $ 99.85
Granted, Weighted Average Grant-Date Fair Value | $ 32.73

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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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- Definition The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to 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)(iv)(3) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Gross number of share options (or share units) granted during the period. + References No definition available. + 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Number of options outstanding, including both vested and non-vested options. + 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 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 Reference 2: 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)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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