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v3.23.4

N-2 | Jan. 24, 2024
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Cover [Abstract] |
Entity Central Index Key | 0000357173
Amendment Flag | false
Securities Act File Number | 000-10537
Document Type | 8-K
Entity Registrant Name | OLD SECOND BANCORP INC
Entity Address, Address Line One | 37 South River Street
Entity Address, City or Town | Aurora
Entity Address, State or Province | IL
Entity Address, Postal Zip Code | 60507
City Area Code | 630
Local Phone Number | 892-0202
Entity Emerging Growth Company | false

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