Noninterest Income (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Noninterest income
Mortgage banking	$ 8,411	$ 16,921	$ 48,502
Net gains (losses) on investment securities	(24,643)		125
Bank-owned life insurance income	877	836	793
Total noninterest income	80,229	111,223	147,387
Retirement and benefit services
Noninterest income
Revenue	65,294	67,135	71,709
Wealth management
Noninterest income
Revenue	21,855	20,870	21,052
Deposit Account
Noninterest income
Revenue	1,280	1,434	1,395
Interchange fees
Noninterest income
Revenue	2,222	2,246	2,180
Misc. transactional fees
Noninterest income
Revenue	1,433	1,429	1,218
Other noninterest income
Noninterest income
Revenue	$ 3,500	$ 352	$ 413

The amount of non interest income on mortgage banking.

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Earnings on or other increases in the value of the cash surrender value of bank owned life insurance policies.

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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity) and investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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