FDIC-Acquired Loans and Loss Sharing Agreements - Fair Value and Expected Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
FDIC-Acquired Loans and Loss Sharing Agreements
Increase in accretable yield due to increased cash flow expectations	$ 12,323	$ 5,202

Represents the monetary amount of Increase in accretable yield due to increased cash flow expectations, during the indicated time period.

No definition available.

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Namespace Prefix:	gsbc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration