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Fair value of unvested restricted stock awards.

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Share based compensation arrangement by share based payment award earned under return on average assets in period.

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Share based compensation arrangement by share based payment award equity instruments other than options expected to vest grants in period.

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- Definition

Aggregate number of common shares reserved for future issuance.

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Face amount or stated value per share of common stock.

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

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Amount of cash inflow 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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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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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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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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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own 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 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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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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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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Expected term of 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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Number of options vested.

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

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Share-Based Compensation - Additional Information (Details) - USD ($)	1 Months Ended		12 Months Ended
	Feb. 28, 2025	Oct. 30, 2014	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Jun. 30, 2017	Oct. 31, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, voting par value			$ 0.01	$ 0.01
Stock option compensation expense			$ 0	$ 0	$ 0
Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of options exercised			345,519	59,153	224,640
Restricted Shares \| Threshold performance
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares vest on grant date			294,819
Restricted Shares \| Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of restricted voting common stock granted			376,799
Common stock, voting par value			$ 0.01
Restricted Shares \| Common Stock \| Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of restricted voting common stock granted	323,488
Common stock, voting par value	$ 0.01
Restricted Shares \| Common Stock \| Each Anniversary of Grant Date Over Four Years \| Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period	3 years
Restricted Shares \| Common Stock \| Each Anniversary of Grant Date Vest Over Three Years
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period			3 years
Restricted Shares \| Common Stock \| Each Anniversary of Grant Date Vest Over Three Years \| Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of restricted voting common stock granted	245,413
Restricted Shares \| Common Stock \| Third Anniversary of Grant Date
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares vest on grant date			12,861
Restricted Shares \| Common Stock \| Third Anniversary of Grant Date \| Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares vest on grant date	9,109
Restricted Shares \| Common Stock \| First Anniversary Of Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares vest on grant date			3,083
Performance-based Restricted Shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of restricted voting common stock granted			66,036
Period for number of shares earned under return on average assets			3 years
Performance-based Restricted Shares \| Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of restricted voting common stock granted	68,966
Period for number of shares earned under return on average assets	3 years
Performance Shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk-free interest rate			4.47%	4.42%
Simulation term			2 years 10 months 6 days	2 years 10 months 6 days
Share price			$ 20.18	$ 25.2
Performance Shares [Member] \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected volatility			33.68%	39.80%
Performance Shares [Member] \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected volatility			29.28%	38.11%
Omnibus Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common stock reserved for issuance						2,600,000
Number of common shares available for future grants			813,089
Omnibus Plan \| Restricted Shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of restricted voting common stock granted			376,799
Restricted shares vested			244,548	238,638	234,603
Fair value of restricted shares, vested			$ 5,200,000	$ 5,700,000	$ 5,900,000
Fair value of unvested restricted stock awards			$ 21,800,000
Share price			$ 23.04	$ 24.24
Number of shares outstanding			751,127	627,271
Omnibus Plan \| Time Options Grants \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period			4 years
Omnibus Plan \| Time Options Grants \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period			1 year
BYB Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common shares available for future grants						0
Number of options granted		1,846,968
Number of shares outstanding			334,423	768,564
Number of options exercised			434,141	0	568,484
Proceeds from the exercise of stock options			$ 2.6		$ 470,000
Tax benefit from exercise of stock options			$ 1.6		$ 2,300,000
Options vested				0
BYB Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common shares available for future grants							2,476,122
BYB Plan \| Time Options Grants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award contractual term			10 years
BYB Plan \| Time Options Grants \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period			5 years
BYB Plan \| Time Options Grants \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period			1 year
BYB Plan \| Performance Options Grants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award contractual term				10 years
BYB Plan \| Performance Options Grants \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period				5 years
BYB Plan \| Performance Options Grants \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period				1 year
FEB Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares outstanding			45,449	103,135
Number of options exercised			57,686	59,153	7,559
Proceeds from the exercise of stock options			$ 675,000	$ 659,000	$ 80,000
Tax benefit from exercise of stock options			$ 252,000	$ 158,000	$ 25,000
Conversion calculation percentage			4.725%