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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, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options exercised, Number of Shares	(13,626)	(28,832)	(64,013)	(144,262)
Director deferred stock units outstanding [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance, Number of Shares/Units			45,661
Granted, Number of Units			8,503
Ending Balance, Number of Shares/Units	54,164		54,164
Beginning Balance, Weighted-Average Grant-Date Fair Value			$ 87.15
Granted Weighted-Average Grant-Date Fair Value			103.47
Ending Balance, Weighted-Average Grant-Date Fair Value	$ 89.71		$ 89.71
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			465,319
Granted, Number of Units			2,594
Stock Awards exercised/vested, Number of Shares			(1,957)
Forfeited/expired, Number of Shares/Units			(1,415)
Ending Balance, Number of Shares/Units	464,541		464,541
Beginning Balance, Weighted-Average Grant-Date Fair Value			$ 105.36
Granted Weighted-Average Grant-Date Fair Value			128.42
Stock Award Exercised/Vested, Weighted Average Grant Date Fair Value			91.96
Forfeited/Expired, Weighted-Average Price			116.02
Ending Balance, Weighted-Average Grant-Date Fair Value	$ 105.52		$ 105.52
Stock Options Outstanding [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance, Number of Shares			616,227
Stock options exercised, Number of Shares			(33,905)
Ending Balance, Number of Shares	582,322		582,322
Beginning Balance, Weighted-Average Exercise Price			$ 71.27
Stock options exercised, Weighted-Average Exercise Price			72.13
Ending Balance, Weighted-Average Exercise Price	$ 71.22		$ 71.22
Maximum [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance, Number of Shares/Units			213,749
Stock Awards exercised/vested, Number of Shares			(28,151)
Forfeited/expired, Number of Shares/Units			(18,254)
Ending Balance, Number of Shares/Units	167,344		167,344
Beginning Balance, Weighted-Average Grant-Date Fair Value			$ 96.20
Stock Award Exercised/Vested, Weighted Average Grant Date Fair Value			85.74
Forfeited/Expired, Weighted-Average Price			85.74
Ending Balance, Weighted-Average Grant-Date Fair Value	$ 99.10		$ 99.10