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Disclosures About Fair Value of Plan Assets (Details) - Southern Bank 401(k) Retirement Plan (the Plan) - USD ($)	Jun. 30, 2025	Jun. 30, 2024
EBP, Investment, Fair Value and NAV [Line Items]
Fair value measurements of assets	$ 69,533,358	$ 56,940,813
Quoted Prices in Active Markets for Identical Assets (Level 1)
EBP, Investment, Fair Value and NAV [Line Items]
Fair value measurements of assets	69,533,358	56,940,813
Company security
EBP, Investment, Fair Value and NAV [Line Items]
Fair value measurements of assets	22,874,722	18,529,431
Company security | Quoted Prices in Active Markets for Identical Assets (Level 1)
EBP, Investment, Fair Value and NAV [Line Items]
Fair value measurements of assets	22,874,722	18,529,431
Mutual funds
EBP, Investment, Fair Value and NAV [Line Items]
Fair value measurements of assets	44,494,883	36,923,067
Mutual funds | Quoted Prices in Active Markets for Identical Assets (Level 1)
EBP, Investment, Fair Value and NAV [Line Items]
Fair value measurements of assets	44,494,883	36,923,067
Money market fund
EBP, Investment, Fair Value and NAV [Line Items]
Fair value measurements of assets	2,163,753	1,488,315
Money market fund | Quoted Prices in Active Markets for Identical Assets (Level 1)
EBP, Investment, Fair Value and NAV [Line Items]
Fair value measurements of assets	$ 2,163,753	$ 1,488,315

X

- Definition

Fair value of investment, excluding plan interest in master trust, held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Includes, but is not limited to, derivative, investment measured at net asset value per share as practical expedient, and insurance contract not meeting fully-benefit responsive investment criteria.

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