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- Definition

Exercise Price Of Stock Options Percent Of Fair Market Value Of Share Of Common Stock On Date Of Grant.

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Number of years options expire.

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Period for options to expire from date of grant.

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Period Of Service From Grant Date Stock Options Awarded Not Subject To Forfeiture

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- Definition

Share-based compensation arrangement by share based payment award options exercised in period intrinsic value.

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- Definition

Share based compensation arrangement by share based payment award options grants in period exercise percentage year one.

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Share based compensation arrangement by share based payment award options grants in period exercise percentage year three.

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Share based compensation arrangement by share based payment award options grants in period exercise percentage year two.

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Stock Option Plans [Line Items]

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Weighted Average Period

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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=120381028&loc=d3e5070-113901

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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).

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-Name Accounting Standards Codification
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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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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.

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- Definition

Value, after forfeiture, of shares granted under share-based payment arrangement. Excludes employee stock ownership plan (ESOP).

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Stock Option Plans - Additional information (Detail) - USD ($) $ / shares in Units, $ in Millions				12 Months Ended
	Mar. 16, 2021	Mar. 12, 2020	Mar. 14, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Stock Option Plans [Line Items]
Compensation expense related to stock option grants				$ 17.5	$ 13.6	$ 14.0
Total intrinsic value of options exercised				127.4	$ 106.4	$ 77.9
Total unrecognized compensation cost related to nonvested options				$ 47.1
Weighted average period, years				4 years
Black-Scholes Option Pricing Model [Member]
Stock Option Plans [Line Items]
Weighted average fair value per option for all options				$ 23.38	$ 9.99	$ 10.71
Long Term Incentive Plan [Member]
Stock Option Plans [Line Items]
Maximum number of shares available				1,800,000
Shares available for grant				9,500,000
Long Term Incentive Plan [Member] \| Maximum [Member]
Stock Option Plans [Line Items]
Minimum exercise price of stock options, percent of fair market value of a share of common stock on the date of grant				100.00%
Maximum period for the exercise of stock options, years				7 years	7 years	7 years
Long Term Incentive Plan [Member] \| Minimum [Member]
Stock Option Plans [Line Items]
Period of service from grant date stock options awarded not subject to forfeiture				2 years	2 years	2 years
Long Term Incentive Plan [Member] \| Minimum [Member] \| Executive Officer [Member]
Stock Option Plans [Line Items]
Minimum age of employee with not subject to award forfeiture on condition compliance				55 years	55 years	55 years
2017 Long Term Incentive Plan [Member]
Stock Option Plans [Line Items]
Number Of Periods Options Expire				7 years
2017 Long Term Incentive Plan [Member] \| Officer and Key Employees [Member]
Stock Option Plans [Line Items]
Shares available for grant	1,640,000	1,590,740	1,283,300
Stock options granted, exercise percentage, on the third anniversary date of the grant	34.00%	34.00%	34.00%
Stock options granted, exercise percentage, on the fourth anniversary date of the grant	33.00%	33.00%	33.00%
Stock options granted, exercise percentage, on the fifth anniversary date of the grant	33.00%	33.00%	33.00%