Shareholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		12 Months Ended				260 Months Ended	360 Months Ended
	May 05, 2020	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2016	Dec. 31, 2023	Dec. 31, 2023
Class of Stock [Line Items]
Cumulative shares repurchased							149,644
Issuance of shares under stock purchase plan						14,814
Total intrinsic value of options exercised		$ 46,000	$ 34,000	$ 82,000
Total unrecognized share-based compensation cost		$ 53,000				$ 53,000	$ 53,000
Unrecognized share-based compensation cost, weighted average period		1 year 8 months 12 days
The Amended 2017 Plan
Class of Stock [Line Items]
Shares authorized for grant	5,500
Weighted average fair value of award granted during the period		$ 113.28	$ 102.65	$ 113.82
Shares available for granting of awards		1,577				1,577	1,577
The Amended 2017 Plan | Upper End | Director
Class of Stock [Line Items]
Fair value of annual equity award grant per participant		$ 600
The Amended 2017 Plan | Upper End | Board of Directors Chairman
Class of Stock [Line Items]
Fair value of annual equity award grant per participant		$ 800
Restricted Stock Units (RSUs)
Class of Stock [Line Items]
Award vesting period	3 years
Number of common stock issued per unit based award upon vesting		100.00%
Weighted average fair value of award granted during the period		$ 113.28
Number of shares, unvested		642	707			642	642
Shares granted		365
Weighted average grant date fair value of shares unvested		$ 109.78	$ 99.09			$ 109.78	$ 109.78
Number of unsettled shares, vested		410
Weighted average grant date fair value of shares vested		$ 94.54
Restricted Shares
Class of Stock [Line Items]
Weighted average fair value of award granted during the period		$ 113.24
Number of shares, unvested		0				0	0
Shares granted		14
Performance Shares
Class of Stock [Line Items]
Number of common stock issued per unit based award upon vesting		100.00%
Number of shares, unvested		164				164	164
Shares granted		78	84	75
Maximum Adjustment Factor		200.00%
Minimum Adjustment Factor		50.00%
Shares issued if minimum performance thresholds are not achieved		0
Weighted average grant date fair value of shares unvested		$ 113.54				$ 113.54	$ 113.54
Number of unsettled shares, vested		114
Weighted average grant date fair value of shares vested		$ 113.71
Employee Stock Option Plan | Upper End
Class of Stock [Line Items]
Maximum contractual term					10 years
Employee Stock Purchase Plan
Class of Stock [Line Items]
Shares authorized for grant		15,305				15,305	15,305
Purchase price percentage of fair market value		85.00%
Amount withheld employee stock purchase plan		$ 25,125				$ 25,125	$ 25,125