Stock Incentive Plans - Additional Information (Detail)	12 Months Ended
Dec. 31, 2019 USD ($) Installment shares	Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2017 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
New grants of stock option \| shares	0
Outstanding options expiration period from the date of grant	10 years
Share-based compensation expense included in selling, general and administrative expenses	$ 7,200,000	$ 5,500,000	$ 4,200,000
Share-based compensation, income tax benefits	$ 1,300,000	$ 1,500,000	$ 1,500,000
2019 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reserved for issuance \| shares	300,000
Percentage in payroll deductions to acquire shares	15.00%
Discount rate of fair market value available for share purchase	85.00%
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vest period	8 years
Options exercisable period after date of grant	10 years
Weighted average fair value of stock options, granted \| $ / shares		$ 36.41
Stock options granted with an exercise price below market price \| shares	0	0	0
Intrinsic value of stock options exercised	$ 3,800,000	$ 2.5	$ 479,000
Fair value of shares vested during the period	312,000	312,000	328,000
Unrecognized compensation expense	$ 3,900,000
Weighted average remaining amortization period	6 years 2 months 12 days
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options exercisable period after date of grant	1 year
Fair value of shares vested during the period	$ 5,800,000	4,000,000	3,300,000
Unrecognized compensation expense	$ 9,700,000
Weighted average remaining amortization period	2 years 7 months 6 days
Number of equal annual installments in which restricted stock units generally vest \| Installment	4
Performance Share Units (“PSUs”) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of shares vested during the period	$ 296,000	$ 0	$ 0
Vesting period	3 years
Maximum payout percentage	200.00%
Two Thousand And Fifteen Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reserved for issuance \| shares	1,000,000
Aggregate number of shares for which incentive stock options may be granted under the Plan \| shares	900,000
2009 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant \| shares	427,408

Maximum payout percentage.

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Share based compensation arrangement by share based payment award number of shares available for grant under stock incentive plan.

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Share-based compensation arrangement by share-based payment award options grants in period gross at below market price.

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Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Exercisable Period From Date Of Grant

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

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Aggregate number of common shares reserved for future issuance.

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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 tax benefit from exercise of option under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Discount rate from fair value on offering date that participants pay for shares.

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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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The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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