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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Deferred, Number of Annual Distribution Installments

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Share based compensation arrangement by share based payment award equity instruments other than options non cash compensation.

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Share based compensation arrangement by share based payment award equity instruments other than options potential vest, maximum.

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Share based compensation arrangement by share based payment award equity Instruments other than options potential vest minimum.

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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 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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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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 weighted average fair value at grant date for nonvested equity-based awards issued 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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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award.

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

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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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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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Percentage of vesting of award under share-based payment arrangement.

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Intrinsic value of outstanding award under share-based payment arrangement. Excludes share and unit options.

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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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Share-based compensation plans - Additional Information (Details) $ / shares in Units, $ in Thousands	12 Months Ended			48 Months Ended
	Dec. 31, 2021 USD ($) installment $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2019	Apr. 17, 2019 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares of common stock issued (in shares) \| shares					12,000,000
Shares available for grant (in shares) \| shares	8,494,373
Compensation cost for share-based payment arrangements	$ 22,608	$ 10,607	$ 14,334
Related tax benefit recognized in net income	5,715	2,686	3,500
Additional net excess tax benefit realized	1,110	2,528	3,520
Noncash stock-based compensation associated performance contingent restricted stock units	11,477	2,023	5,171
Compensation deferrals in current year	$ 2,507	$ 2,593	$ 2,585
Restricted Stock Units (RSUs) \| Executive Officers and Key Management Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum vesting period	3 years
Restricted Stock Units (RSUs) \| Executive Officers and Key Management Employees \| Share-based Compensation Award, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.33%
Restricted Stock Units (RSUs) \| Executive Officers and Key Management Employees \| Share-based Compensation Award, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.33%
Restricted Stock Units (RSUs) \| Executive Officers and Key Management Employees \| Share-based Compensation Award, Tranche Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.33%
Restricted Stock Units (RSUs) \| Executives and Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum vesting period	5 years
Granted, weighted-average grant date fair value (usd per share) \| $ / shares	$ 57.77	$ 54.16	$ 57.76
Fair value of vested units	$ 4,063	$ 3,277	$ 3,217
Restricted Stock Units (RSUs) \| Executives and Directors \| Share-based Compensation Award, Tranche Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.33%
Restricted Stock Units (RSUs) \| Executives and Directors \| Share-based Compensation Award, Tranche Four
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.33%
Restricted Stock Units (RSUs) \| Executives and Directors \| Share-based Compensation Award, Tranche Five
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.33%
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, weighted-average grant date fair value (usd per share) \| $ / shares	$ 57.77
Vested units in period (in shares) \| shares	0
Restricted Stock Awards \| Executives and Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Noncash stock-based compensation associated performance contingent restricted stock units	$ 8,278	$ 4,549	$ 3,351
Total unrecognized compensation cost related to nonvested awards	$ 8,061
Weighted-average period	46 months
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, weighted-average grant date fair value (usd per share) \| $ / shares	$ 55.95	$ 52	$ 56.04
Total unrecognized compensation cost related to nonvested awards	$ 14,259
Weighted-average period	21 months
Performance period	3 years
Number of common shares to be converted into for each share upon conversion	1
Performance Shares \| 2021 PCSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period	3 years
Total performance contingent restricted stock units vested , minimum (in shares) \| shares	0
Total performance contingent restricted stock units, maximum (in shares) \| shares	285,724
Performance Shares \| 2020 PCSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period	3 years
Total performance contingent restricted stock units vested , minimum (in shares) \| shares	0
Total performance contingent restricted stock units, maximum (in shares) \| shares	297,648
Performance Shares \| 2019 PCSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of vested units	$ 3,719
Total performance contingent restricted stock units, maximum (in shares) \| shares	64,243
Performance Shares \| 2018 PCSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of vested units		$ 8,288
Vested units in period (in shares) \| shares		139,886
Performance Shares \| 2017 PCSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of vested units			$ 5,217
Vested units in period (in shares) \| shares			84,522
Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.33%
Total unrecognized compensation cost related to nonvested awards	$ 40
Weighted-average period	2 months
Vested units in period (in shares) \| shares	0
Aggregate intrinsic value of options and SARs exercised	$ 2,575	$ 2,771	$ 11,836
Weighted-average fair value of awards granted (usd per share) \| $ / shares			$ 8.3
Weighted average remaining contractual life for SAR's, outstanding	6 years 1 month 6 days
Weighted average remaining contractual life for SAR's, exercisable	5 years 10 months 24 days
Aggregate intrinsic value for SAR's, outstanding	$ 3,598
Aggregate intrinsic value for SAR's, exercisable	$ 2,800
Fair market value of the Company’s stock used to calculate intrinsic value (usd per share) \| $ / shares	$ 57.89
Stock Appreciation Rights (SARs) \| Granted 2015 through 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum vesting period				3 years
Term of award	10 years
Unvested award termination period upon change in control	2 years
Stock Options and Stock Appreciation Rights Sars
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost for share-based payment arrangements	$ 347	$ 1,442	$ 3,227
Deferred Stock Equivalent Units \| Non-employee directors \| Share-based Compensation Award, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of annual distribution installments \| installment	1
Deferred Stock Equivalent Units \| Non-employee directors \| Share-based Compensation Award, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of annual distribution installments \| installment	3
Deferred Stock Equivalent Units \| Non-employee directors \| Share-based Compensation Award, Tranche Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of annual distribution installments \| installment	5