Loans and Allowance for Loan Losses - Troubled Debt Restructured Loans Returned to Accrual Status (Details)	12 Months Ended
Dec. 31, 2019 USD ($)
One- to four-family residential
Troubled Debt Restructurings Returned to Accrual Status	$ 372,000

Represents the monetary amount of Troubled Debt Restructurings Returned to Accrual Status, during the indicated time period.

No definition available.

Name:	gsbc_TroubledDebtRestructuringsReturnedToAccrualStatus
Namespace Prefix:	gsbc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration