GREAT SOUTHERN BANCORP, INC. AND SUBSIDIARIES -- CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) (Parentheticals) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Statements of Comprehensive Income (Parentheticals)
Tax effect of unrealized appreciation (depreciation) on available-for-sale securities, taxes (credit)	$ (52)	$ 1,533
Tax effect reclassification adjustment for gains included in net income, taxes (credit)	0	(26)
Tax effect of change in fair value of cash flow hedge, taxes (credit)	$ (53)	$ (23)

For banks, the amount of interest Income or Loss derived from or related to loans of real estate investments of the financial institution held for development or sale.

No definition available.

Name:	fil_TaxEffectOfUnrealizedAppreciationDepreciationOnAvailableForSaleSecuritiesTaxesCredit
Namespace Prefix:	fil_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration