The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of share options (or share units) exercised during the current period.

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Stock-Based Compensation - Summary of Activity in Corporation's Active Stock Plans (Detail) - $ / shares	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options exercised, Number of Shares	(28,832)	(114,252)	(144,262)	(628,076)
Director deferred stock units outstanding [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance, Number of Shares/Units			56,301
Granted, Number of Units			5,382
Stock Awards exercised/vested, Number of Shares			(16,022)
Ending Balance, Number of Shares/Units	45,661		45,661
Beginning Balance, Weighted-Average Grant-Date Fair Value			$ 79.21
Granted Weighted-Average Grant-Date Fair Value			133.67
Stock Award Exercised/Vested, Weighted Average Grant Date Fair Value			74.89
Ending Balance, Weighted-Average Grant-Date Fair Value	$ 87.15		$ 87.15
Non-Vested Stock Awards/Stock Units Outstanding [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance, Number of Shares/Units			449,337
Granted, Number of Units			3,460
Forfeited/expired, Number of Shares/Units			(3,167)
Ending Balance, Number of Shares/Units	449,630		449,630
Beginning Balance, Weighted-Average Grant-Date Fair Value			$ 93.05
Granted Weighted-Average Grant-Date Fair Value			132.72
Forfeited/Expired, Weighted-Average Price			94.57
Ending Balance, Weighted-Average Grant-Date Fair Value	$ 93.35		$ 93.35
Stock Options Outstanding [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance, Number of Shares			877,681
Stock options exercised, Number of Shares			(103,060)
Ending Balance, Number of Shares	774,621		774,621
Beginning Balance, Weighted-Average Exercise Price			$ 69.02
Stock options exercised, Weighted-Average Exercise Price			62.97
Ending Balance, Weighted-Average Exercise Price	$ 69.83		$ 69.83
Maximum [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance, Number of Shares/Units			202,460
Stock Awards exercised/vested, Number of Shares			(25,180)
Forfeited/expired, Number of Shares/Units			(16,058)
Ending Balance, Number of Shares/Units	161,222		161,222
Beginning Balance, Weighted-Average Grant-Date Fair Value			$ 84.71
Stock Award Exercised/Vested, Weighted Average Grant Date Fair Value			87.18
Forfeited/Expired, Weighted-Average Price			87.18
Ending Balance, Weighted-Average Grant-Date Fair Value	$ 84.08		$ 84.08