Document and Entity Information - $ / shares		3 Months Ended
May 06, 2019	Mar. 31, 2019
Details
Registrant Name		GREAT SOUTHERN BANCORP, INC.
Registrant CIK		0000854560
SEC Form		10-Q
Period End date		Mar. 31, 2019
Fiscal Year End		--12-31
Trading Symbol		gsbc
Tax Identification Number (TIN)		431524856
Number of common stock shares outstanding	14,196,383
Filer Category		Accelerated Filer
Current with reporting		Yes
Small Business		false
Emerging Growth Company		false
Amendment Flag		false
Document Fiscal Year Focus		2019
Document Fiscal Period Focus		Q1
Entity File Number		0-18082
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, Description		Common Stock
Name of Exchange on Which Registered		The NASDAQ Stock Market LLC
Entity Listing, Par Value Per Share	$ 0.01

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The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

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Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

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