Document and Entity Information - $ / shares		6 Months Ended
Aug. 05, 2019	Jun. 30, 2019
Details
Registrant CIK		0000854560
Fiscal Year End		--12-31
Registrant Name		GREAT SOUTHERN BANCORP, INC.
SEC Form		10-Q
Period End date		Jun. 30, 2019
Trading Symbol		GSBC
Trading Exchange		NASDAQ
Tax Identification Number (TIN)		43-1524856
Number of common stock shares outstanding	14,212,579
Filer Category		Accelerated Filer
Current with reporting		Yes
Interactive Data Current		Yes
Shell Company		false
Small Business		false
Emerging Growth Company		false
Entity File Number		0-18082
Entity Incorporation, State or Country Code		MD
Entity Address, Address Line One		1451 E. Battlefield
Entity Address, City or Town		Springfield
Entity Address, State or Province		MO
Entity Address, Postal Zip Code		65804
City Area Code		417
Local Phone Number		887-4400
Title of 12(b) Security		Common Stock
Entity Listing, Par Value Per Share	$ 0.01
Amendment Flag		false
Document Fiscal Year Focus		2019
Document Fiscal Period Focus		Q2
Document Quarterly Report		true
Document Transition Report		false

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Area code of city

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End date of current fiscal year in the format --MM-DD.

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Fiscal period values are FY, Q1, Q2, and Q3. 1st, 2nd and 3rd quarter 10-Q or 10-QT statements have value Q1, Q2, and Q3 respectively, with 10-K, 10-KT or other fiscal year statements having FY.

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This is focus fiscal year of the document report in CCYY format. For a 2006 annual report, which may also provide financial information from prior periods, fiscal 2006 should be given as the fiscal year focus. Example: 2006.

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The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD.

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Boolean flag that is true only for a form used as an quarterly report.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Boolean flag that is true only for a form used as a transition report.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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Address Line 1 such as Attn, Building Name, Street Name

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Name of the City or Town

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Code for the postal or zip code

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Name of the state or province.

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A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Indicate number of shares or other units outstanding of each of registrant's classes of capital or common stock or other ownership interests, if and as stated on cover of related periodic report. Where multiple classes or units exist define each class/interest by adding class of stock items such as Common Class A [Member], Common Class B [Member] or Partnership Interest [Member] onto the Instrument [Domain] of the Entity Listings, Instrument.

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Indicate 'Yes' or 'No' whether registrants (1) have filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that registrants were required to file such reports), and (2) have been subject to such filing requirements for the past 90 days. This information should be based on the registrant's current or most recent filing containing the related disclosure.

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Indicate if registrant meets the emerging growth company criteria.

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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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No definition available.

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Indicate whether the registrant is one of the following: Large Accelerated Filer, Accelerated Filer, Non-accelerated Filer. Definitions of these categories are stated in Rule 12b-2 of the Exchange Act. This information should be based on the registrant's current or most recent filing containing the related disclosure.

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Two-character EDGAR code representing the state or country of incorporation.

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Boolean flag that is true when the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The par value per share of security quoted in same currency as Trading currency. Example: '0.01'.

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The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

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Boolean flag that is true when the registrant is a shell company as defined in Rule 12b-2 of the Exchange Act.

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Indicates that the company is a Smaller Reporting Company (SRC).

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The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

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Local phone number for entity.

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Title of a 12(b) registered security.

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Name of the Exchange on which a security is registered.

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Trading symbol of an instrument as listed on an exchange.

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