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Aggregate number of common shares reserved for future issuance.

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Aggregate dividends paid during the period for each share of common stock outstanding.

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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 cost to be recognized for option under share-based payment arrangement.

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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

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The amount of plan compensation cost recognized during the period.

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

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Number, after shares used to satisfy grantee's tax withholding obligation for award under share-based payment arrangement, of restricted shares issued. Excludes cash used to satisfy grantee's tax withholding obligation.

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

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Number of additional shares authorized for issuance under share-based payment arrangement.

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Purchase price of common stock expressed as a percentage of its fair value.

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Stock-based compensation - Narrative (Detail) - USD ($)											12 Months Ended
Stock-based compensation - Narrative (Detail) - USD ($)	Apr. 05, 2022	Dec. 22, 2021	Sep. 24, 2021	Jun. 23, 2021	Mar. 19, 2021	Dec. 23, 2020	Sep. 23, 2020	Jun. 26, 2020	Mar. 18, 2020	Apr. 05, 2019	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	May 09, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation cost											$ 75,836,000	$ 80,548,000	$ 72,709,000
Income tax benefits recognized											$ 21,863,000	$ 21,857,000	21,832,000
Options granted, contractual period, years											10 years
Dividends paid per share (in dollars per share)		$ 0.1075	$ 0.1075	$ 0.1075	$ 0.1075	$ 0.0975	$ 0.0975	$ 0.0975	$ 0.0975		$ 0.125	$ 0.1075
Cash received from the exercise of stock option											$ 14,701,000	$ 23,168,000	14,062,000
Tax benefits from the exercise of stock option											$ 2,398,000	6,927,000	7,381,000
Restricted Stock Unit vesting right (in shares)											1
Restricted Stock Unit vesting right, fair value (in shares)											1
Performance Units vesting right (in shares)											1
Performance Units vesting right, fair value (in shares)											1
Unrecognized stock-based compensation cost for options											$ 18,288,000
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excess tax benefit											$ 1,543,000	$ 4,191,000	$ 7,310,000
Weighted average remaining requisite vesting period											2 years 10 months 24 days
Restricted Share Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average remaining requisite vesting period											2 years
Unrecognized stock-based compensation cost											$ 11,565,000
Restricted Share Units (RSUs) \| Vested in 2020, excluding directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Net settlement on vesting of restricted share units (Note 18) (in shares)											49,446		385,197
Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average remaining requisite vesting period											1 year 8 months 12 days
Unrecognized stock-based compensation cost											$ 63,734,000
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of fair value per share allowed to eligible employees to purchase through payroll deductions											90.00%
Maximum percentage of employee's base salary allowed to be purchased											15.00%
Maximum dollar amount of common shares allowed to be purchased											$ 25,000
Common shares reserved for issuance (in shares)											4,200,000
Issuance of common shares under the employee stock purchase plan (Note 18) (in shares)											324,783	285,657	315,245
Compensation expense for ESPP											$ 1,537,000	$ 1,420,000	$ 1,299,000
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award, vesting period, years											3 years
Minimum \| Restricted Share Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award, vesting period, years											3 months
Minimum \| Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award, vesting period, years											6 months
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award, vesting period, years											5 years
Maximum \| Restricted Share Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award, vesting period, years											4 years
Maximum \| Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award, vesting period, years											3 years
2007 Omnibus Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common shares authorized for issuance (in shares)	26,500,000									23,000,000	23,858,823
Amended Omnibus Plan, increase in number of common shares authorized for issuance (in shares)	3,500,000									8,000,000
2017 Omnibus Incentive Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common shares authorized for issuance (in shares)														15,000,000