Face (par) amount of debt instrument at time of issuance.

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REGULATORY CAPITAL - Narrative (Details) - USD ($) $ in Millions		12 Months Ended
	Jun. 02, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	May 25, 2017
Regulatory Capital
Busey Bank paid dividends to the Company, amount received		$ 95.0	$ 60.0	$ 122.0
Subordinated Debt \| 4.75% notes maturing May 25, 2027
Regulatory Capital
Principal balance					$ 60.0
Subordinated Debt \| 5.000% notes maturing June 15, 2032
Regulatory Capital
Principal balance	$ 100.0
Fixed to floating interest rate	5.00%