v3.25.3

Cover	Oct. 28, 2025
Document Information [Line Items]
Document Type	8-K
Document Period End Date	Oct. 28, 2025
Entity Registrant Name	First Busey Corporation
Entity Incorporation, State or Country Code	NV
Entity File Number	0-15950
Entity Tax Identification Number	37-1078406
Entity Address, Address Line One	11440 Tomahawk Creek Parkway
Entity Address, City or Town	Leawood
Entity Address, State or Province	KS
Entity Address, Postal Zip Code	66211
City Area Code	(217)
Local Phone Number	365-4544
Written Communications	false
Soliciting Material	false
Pre-commencement Tender Offer	false
Pre-commencement Issuer Tender Offer	false
Entity Emerging Growth Company	false
Amendment Flag	false
Entity Central Index Key	0000314489
Common Stock, $0.001 par value
Document Information [Line Items]
Title of 12(b) Security	Common Stock, $0.001 par value
Trading Symbol	BUSE
Security Exchange Name	NASDAQ
Depositary Shares, each representing a 1/40th interest in a share of 8.25% Fixed-Rate Series B Non-Cumulative Perpetual Preferred Stock, $0.001 par value
Document Information [Line Items]
Title of 12(b) Security	Depositary Shares, each representing a 1/40th interest in a share of 8.25% Fixed-Rate Series B Non-Cumulative Perpetual Preferred Stock
Trading Symbol	BUSEP
Security Exchange Name	NASDAQ

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For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.

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The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

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A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

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FIRST BUSEY CORP /NV/ 8-K