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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, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options exercised, Number of Shares	(36,942)	(38,452)	(140,878)	(122,628)
Deferred Stock Units Outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance, Number of Shares/Units			52,779
Granted, Number of Units			8,760
Ending Balance, Number of Shares/Units	61,539		61,539
Beginning Balance, Weighted-Average Grant-Date Fair Value			$ 95.37
Granted Weighted-Average Grant-Date Fair Value			116.47
Ending Balance, Weighted-Average Grant-Date Fair Value	$ 98.38		$ 98.38
Non-Vested Restricted Stock Units Outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance, Number of Shares/Units			507,862
Granted, Number of Units			2,185
Stock Awards exercised/vested, Number of Shares			(3,322)
Forfeited/expired, Number of Shares/Units			(2,825)
Ending Balance, Number of Shares/Units	503,900		503,900
Beginning Balance, Weighted-Average Grant-Date Fair Value			$ 113.72
Granted Weighted-Average Grant-Date Fair Value			126.04
Stock Award Exercised/Vested, Weighted Average Grant Date Fair Value			132.18
Forfeited/Expired, Weighted-Average Price			111.32
Ending Balance, Weighted-Average Grant-Date Fair Value	$ 113.66		$ 113.66
Stock Options Outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance, Number of Shares			183,976
Stock options exercised, Number of Shares			(91,470)
Ending Balance, Number of Shares	92,506		92,506
Beginning Balance, Weighted-Average Exercise Price			$ 65.11
Stock options exercised, Weighted-Average Exercise Price			65.11
Ending Balance, Weighted-Average Exercise Price	$ 65.11		$ 65.11
Maximum [Member] \| Performance Stock Units Outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance, Number of Shares/Units			230,657
Stock Awards exercised/vested, Number of Shares			(46,086)
Ending Balance, Number of Shares/Units	184,571		184,571
Beginning Balance, Weighted-Average Grant-Date Fair Value			$ 103.65
Stock Award Exercised/Vested, Weighted Average Grant Date Fair Value			121.46
Ending Balance, Weighted-Average Grant-Date Fair Value	$ 99.20		$ 99.20