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Stock-Based Compensation - Summary of Stock-Based Compensation Grants (Detail) | 6 Months Ended
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Jun. 30, 2021 $ / shares shares
Time Based Restricted Stock Units [Member] |  |
Stock Awards Granted | shares | 23,568 |
Weighted-Average Grant Price Per Share | $ / shares | $ 103.80 |
Performance Based Restricted Stock Units [Member] |  |
Stock Awards Granted | shares | 36,522 | [1]
Weighted-Average Grant Price Per Share | $ / shares | $ 86.26 | [1]
Stock Appreciation Rights [Member] |  |
Stock Awards Granted | shares | 15,029 |
Weighted-Average Grant Price Per Share | $ / shares | $ 104.56 |
[1] | Includes 26,511 of target performance-based restricted stock unit awards granted during the six months ended June 30, 2021, and adjustments of 4,813, (887) and 6,085 to grants due to the actual performance level achieved for restricted stock and restricted stock units awarded in 2020, 2019, and 2018, respectively.

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- Definition Share based compensation arrangement by share based payment award non options equity instruments granted weighted average grant price. + References No definition available. + Details
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- Definition The number of grants made 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Details
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