EARNINGS PER SHARE (Details) - shares	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
EARNINGS PER SHARE
Options to purchase shares of common stock outstanding not included in computation of diluted earnings per share because exercise price greater than average market price	352,488	568,551

Represents the Options to purchase shares of common stock outstanding not included in computation of diluted earnings per share because exercise price greater than average market price (number of shares), during the indicated time period.

No definition available.

Name:	gsbc_OptionsToPurchaseSharesOfCommonStockOutstandingNotIncludedInComputationOfDilutedEarningsPerShareBecauseExercisePriceGreaterThanAverageMarketPrice
Namespace Prefix:	gsbc_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration