Noninterest Income (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Noninterest income
Mortgage banking	$ 48,502	$ 61,641	$ 25,805
Net gains (losses) on investment securities	125	2,737	357
Bank-owned life insurance income	793	797	803
Total noninterest income	147,387	149,371	114,194
Retirement and Benefit Services
Noninterest income
Revenue	71,709	60,956	63,811
Wealth Management
Noninterest income
Revenue	21,052	17,451	15,502
Deposit Account
Noninterest income
Revenue	1,395	1,409	1,772
Interchange Fees
Noninterest income
Revenue	2,180	2,140	1,972
Transactional Fees
Noninterest income
Revenue	1,218	1,246	1,236
Other Noninterest
Noninterest income
Revenue	$ 413	$ 994	$ 2,936

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.

+ References

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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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