Gross number of share options (or share units) assumed from merger during the period.

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Amount of cost to be recognized for 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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Number of shares authorized for issuance under share-based payment arrangement.

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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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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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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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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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

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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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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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Share-Based Compensation - Stock Options (Details)	3 Months Ended	17 Months Ended	38 Months Ended	122 Months Ended
Share-Based Compensation - Stock Options (Details)	Mar. 31, 2022 USD ($) $ / shares shares	Mar. 31, 2022 USD ($) $ / shares shares	Mar. 31, 2022 USD ($) $ / shares shares	Mar. 31, 2022 USD ($) $ / shares shares
Additional disclosures
Intrinsic value of stock option shares exercised \| $	$ 418,000
2004 plan
Additional disclosures
Granted (in shares)				0
2012 plan
Additional disclosures
Granted (in shares)			0
2019 plan
Additional disclosures
Granted (in shares)		0
2020 plan
Share-Based Compensation
Number of shares registered	2,072,245	2,072,245	2,072,245	2,072,245
Stock Options
Share-Based Compensation
Vesting percentage	25.00%
Vesting period	4 years
Expiration period	10 years
Number of shares
Outstanding at the beginning of the period (in shares)	185,125
Assumed stock options and warrants from ACBI merger (in shares)	23,410
Exercised (in shares)	(9,703)
Expired (in shares)	(14)
Outstanding at the end of the period (in shares)	198,818	198,818	198,818	198,818
Exercisable at the end of the period (in shares)	198,818	198,818	198,818	198,818
Weighted-Average Exercise Price
Outstanding at the beginning of the period (in dollars per share) \| $ / shares	$ 63.03
Assumed stock options and warrants from ACBI merger (in dollars per share) \| $ / shares	40.73
Exercised (in dollars per share) \| $ / shares	42.25
Expired (in dollars per share) \| $ / shares	33.02
Outstanding at the end of the period (in dollars per share) \| $ / shares	61.42	$ 61.42	$ 61.42	$ 61.42
Exercisable at the end of the period (in dollars per share) \| $ / shares	$ 61.42	$ 61.42	$ 61.42	$ 61.42
Weighted-Average Remaining Contractual Life
Outstanding at the end of the period	3 years 9 months 10 days
Exercisable at the end of the period	3 years 9 months 10 days
Aggregate Intrinsic Value
Outstanding at the end of the period \| $	$ 4,554,000	$ 4,554,000	$ 4,554,000	$ 4,554,000
Exercisable at the end of the period \| $	$ 4,554,000	4,554,000	4,554,000	4,554,000
Additional disclosures
Granted (in shares)	0
Total unrecognized compensation cost related to non vested stock option grants \| $	$ 0	$ 0	$ 0	$ 0