Document and Entity Information - $ / shares		9 Months Ended
Jun. 30, 2016	Sep. 30, 2017	Nov. 03, 2017
Details
Registrant Name		GREAT SOUTHERN BANCORP, INC.
Registrant CIK		0000854560
SEC Form		10-Q
Period End date		Sep. 30, 2017
Fiscal Year End		--12-31
Trading Symbol		GSBC
Tax Identification Number (TIN)		431524856
Number of common stock shares outstanding			14,058,343
Filer Category		Accelerated Filer
Current with reporting		Yes
Voluntary filer		No
Well-known Seasoned Issuer		No
Amendment Flag		false
Document Fiscal Year Focus		2017
Document Fiscal Period Focus		Q3
Entity Incorporation, State Country Name		Maryland
Entity Address, Address Line One		1451 E. Battlefield
Entity Address, City or Town		Springfield
Entity Address, State or Province		Missouri
Entity Address, Postal Zip Code		65804
City Area Code		417
Local Phone Number		887-4400
Entity Listing, Par Value Per Share	$ 0.01

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