Amount of lease income from operating, direct financing, and sales-type leases. Includes, but is not limited to, variable lease payments, interest income, profit (loss) recognized at commencement, and lease payments paid and payable to lessor.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=124258985&loc=SL77919372-209981

Name:	us-gaap_LeaseIncome
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Leases - Busey as the Lessor (Details) $ in Thousands		12 Months Ended
Leases - Busey as the Lessor (Details) $ in Thousands	May 31, 2021 item	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Lessor, Lease, Description [Line Items]
Lease income \| $		$ 566	$ 228	$ 263
Glenview, IL
Lessor, Lease, Description [Line Items]
Number of office buildings	2
Northbrook, IL
Lessor, Lease, Description [Line Items]
Number of office buildings	1