Amount of tax benefit from the issuance of stock granted under share-based compensation arrangements.

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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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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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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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

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Share-Based Compensation Plans - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized under employee stock purchase plan (in shares)	3,250,000
Shares available for grant or issuance under share-based compensation plans (in shares)	792,726
Compensation expense to be recognized	$ 9,800
Maximum vesting period	3 years
Total intrinsic value of options exercised			$ 1,200
Stock options outstanding (in shares)	0	0	0
Tax benefit from issuance of stock	$ 3,900	$ 2,600	$ 1,900
Excess tax benefit from share-based compensation	1,654	828	191
Awards of Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 12,100	$ 11,100	$ 11,200
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares vested, but issuance deferred (in shares)	49,360
Issuance deferral period	10 years
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares)				20,000
Options exercised (in shares)			20,000
Weighted average price, exercised (in dollars per share)			$ 24.48
Employee Stock Purchase Plan (in shares)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized under employee stock purchase plan (in shares)	3,000,000