Document and Entity Information - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2018	Sep. 13, 2018	Dec. 31, 2017
Details
Registrant Name	SOUTHERN MISSOURI BANCORP, INC.
Registrant CIK	0000916907
SEC Form	10-K
Period End date	Jun. 30, 2018
Fiscal Year End	--06-30
Trading Symbol	smbc
Tax Identification Number (TIN)	431665523
Number of common stock shares outstanding		8,996,584
Public Float			$ 269,500
Filer Category	Accelerated Filer
Current with reporting	Yes
Voluntary filer	No
Well-known Seasoned Issuer	No
Emerging Growth Company	false
Ex Transition Period	true
Amendment Flag	false
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	FY
Entity Incorporation, State Country Name	Missouri
Entity Address, Address Line One	2991 Oak Grove Road
Entity Address, City or Town	Poplar Bluff
Entity Address, State or Province	Missouri
Entity Address, Postal Zip Code	63901
City Area Code	573
Local Phone Number	778-1800

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