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Range of contractual term of option awards.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Gross number of share options (or share units) granted during the period.

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

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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

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

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Stock Compensation - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2025	Sep. 30, 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Proceeds from exercise of stock options							$ 12,793	$ 7,531
Number of options, Outstanding	11,330,004						11,330,004
Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock options exercised	879,000	407,000	975,000	746,000	491,000	664,000
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to non-vested stock compensation awards granted under the Plan	$ 6,200						$ 6,200
Expected remaining weighted average vesting period							2 years 6 months
Non-cash stock-based compensation expense	$ 900			$ 800			$ 3,400	$ 4,500
Common stock granted	0			0			18,700	35,693
Two Thousand Eighteen Stock Incentive Plan [Member] \| Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock shares available for future issuance under the Plan	6,739,236						6,739,236
Options to Purchase Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock options exercised	879,014			745,195			2,260,541	1,901,467
Proceeds from exercise of stock options	$ 5,800			$ 4,000			$ 12,800	$ 7,500
Stock option granted, contractual term	7 years			7 years			7 years	7 years
Common stock unit granted	82,500			40,000			773,903	880,995
Unrecognized compensation expense related to non-vested stock compensation awards granted under the Plan	$ 32,200						$ 32,200
Expected remaining weighted average vesting period							2 years 4 months 24 days
Non-cash stock-based compensation expense	$ 4,800			$ 3,600			$ 15,700	$ 12,600
Stock options to purchase shares of common stock	6,338,132						6,338,132