XML 40 R30.htm IDEA: XBRL DOCUMENT
v3.26.1

INVESTMENT SECURITIES (Tables) | 3 Months Ended
--- | ---
Mar. 31, 2026
INVESTMENT SECURITIES |
Schedule of amortized cost and fair values of securities | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ ​ ​ | March 31, 2026
​ | ​ | ​ | ​ | Gross | ​ | Gross | ​ | ​ | ​
​ | ​ | Amortized | ​ | Unrealized | ​ | Unrealized | ​ | Fair
​ |  | Cost | ​ ​ ​ | Gains | ​ ​ ​ | Losses | ​ ​ ​ | Value
​ |  | (In Thousands)
AVAILABLE-FOR-SALE SECURITIES: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Agency mortgage-backed securities |  | $ | 320,297 |  | $ | 380 |  | $ | 25,920 |  | $ | 294,757
Agency collateralized mortgage obligations | ​ | ​ | 119,018 | ​ | ​ | 771 | ​ | ​ | 5,930 | ​ | ​ | 113,859
States and political subdivisions | ​ | ​ | 53,224 | ​ | ​ | 76 | ​ | ​ | 2,486 | ​ | ​ | 50,814
Small Business Administration securities | ​ | ​ | 59,922 | ​ | ​ | — | ​ | ​ | 5,506 | ​ | ​ | 54,416
​ |  | $ | 552,461 |  | $ | 1,227 |  | $ | 39,842 |  | $ | 513,846
​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | March 31, 2026
​ | ​ | ​ | ​ | ​ | ​ | Amortized | ​ | Gross | ​ | Gross | ​ | ​
​ | ​ | Amortized | ​ | Fair Value | ​ | Carrying | ​ | Unrealized | ​ | Unrealized | ​ | Fair
​ | ​ ​ ​ | Cost | ​ ​ ​ | Adjustment | ​ ​ ​ | Value | ​ ​ ​ | Gains | ​ ​ ​ | Losses | ​ ​ ​ | Value
​ | ​ | (In Thousands)
HELD-TO-MATURITY SECURITIES: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Agency mortgage-backed securities | ​ | $ | 69,377 | ​ | $ | 1,179 | ​ | $ | 70,556 | ​ | $ | — | ​ | $ | 5,820 | ​ | $ | 64,736
Agency collateralized mortgage obligations | ​ |  | 102,711 | ​ |  | (1,778) | ​ |  | 100,933 | ​ |  | — | ​ |  | 10,739 | ​ |  | 90,194
States and political subdivisions | ​ |  | 6,076 | ​ |  | 29 | ​ |  | 6,105 | ​ |  | — | ​ |  | 515 | ​ |  | 5,590
​ | ​ | $ | 178,164 | ​ | $ | (570) | ​ | $ | 177,594 | ​ | $ | — | ​ | $ | 17,074 | ​ | $ | 160,520
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ ​ ​ | December 31, 2025
​ | ​ | ​ | ​ | Gross | ​ | Gross | ​ | ​ | ​
​ | ​ | Amortized | ​ | Unrealized | ​ | Unrealized | ​ | Fair
​ |  | Cost | ​ ​ ​ | Gains | ​ ​ ​ | Losses | ​ ​ ​ | Value
​ |  | (In Thousands)
AVAILABLE-FOR-SALE SECURITIES: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Agency mortgage-backed securities |  | $ | 325,618 |  | $ | 805 |  | $ | 25,174 |  | $ | 301,249
Agency collateralized mortgage obligations | ​ | ​ | 120,465 | ​ | ​ | 933 | ​ | ​ | 6,065 | ​ | ​ | 115,333
States and political subdivisions securities | ​ | ​ | 53,347 | ​ | ​ | 89 | ​ | ​ | 2,038 | ​ | ​ | 51,398
Small Business Administration securities | ​ | ​ | 61,000 | ​ | ​ | 14 | ​ | ​ | 5,163 | ​ | ​ | 55,851
​ |  | $ | 560,430 |  | $ | 1,841 |  | $ | 38,440 |  | $ | 523,831
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ ​ ​ | December 31, 2025
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | Amortized | ​ | Gross | ​ | Gross | ​ | ​ | ​
​ | ​ | Amortized | ​ | Fair Value | ​ | Carrying | ​ | Unrealized | ​ | Unrealized | ​ | Fair
​ | ​ ​ ​ | Cost | ​ ​ ​ | Adjustment | ​ ​ ​ | Value | ​ ​ ​ | Gains | ​ ​ ​ | Losses | ​ ​ ​ | Value
​ | ​ | (In Thousands)
HELD-TO-MATURITY SECURITIES: |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​
Agency mortgage-backed securities | ​ | $ | 69,713 | ​ | $ | 1,313 | ​ | $ | 71,026 | ​ | $ | — | ​ | $ | 5,694 | ​ | $ | 65,332
Agency collateralized mortgage obligations | ​ |  | 103,918 | ​ |  | (1,857) | ​ |  | 102,061 | ​ |  | — | ​ |  | 10,424 | ​ |  | 91,637
States and political subdivisions | ​ |  | 6,086 | ​ |  | 27 | ​ |  | 6,113 | ​ |  | — | ​ |  | 453 | ​ |  | 5,660
​ | ​ | $ | 179,717 | ​ | $ | (517) | ​ | $ | 179,200 | ​ | $ | — | ​ | $ | 16,571 | ​ | $ | 162,629
Schedule of amortized cost and fair value of available-for-sale and held-to-maturity securities by contractual maturity | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Available-for-Sale | ​ | Held-to-Maturity
​ | ​ | Amortized | ​ | Fair | ​ | Amortized | ​ | Fair
​ | ​ ​ ​ | Cost | ​ ​ ​ | Value | ​ ​ ​ | Carrying Value | ​ ​ ​ | Value
​ | ​ | (In Thousands)
One year or less | ​ | $ | — | ​ | $ | — | ​ | $ | — |  | $ | —
After one through two years | ​ | ​ | 1,029 | ​ | ​ | 1,037 | ​ | ​ | — | ​ | ​ | —
After two through three years | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | —
After three through four years | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | —
After four through five years | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | —
After five through fifteen years | ​ | ​ | 26,290 | ​ | ​ | 25,243 | ​ | ​ | 6,105 | ​ | ​ | 5,590
After fifteen years | ​ | ​ | 25,905 | ​ | ​ | 24,534 | ​ | ​ | — | ​ | ​ | —
Securities not due on a single maturity date | ​ | ​ | 499,237 | ​ | ​ | 463,032 | ​ | ​ | 171,489 | ​ | ​ | 154,930
​ | ​ | $ | 552,461 | ​ | $ | 513,846 | ​ | $ | 177,594 |  | $ | 160,520
Schedule of gross unrealized losses and fair value, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | March 31, 2026
​ | ​ | Less than 12 Months | ​ | 12 Months or More | ​ | Total
​ | ​ | Fair | ​ | Unrealized | ​ | Fair | ​ | Unrealized | ​ | Fair | ​ | Unrealized
Description of Securities | ​ ​ ​ ​ | Value | ​ ​ ​ | Losses | ​ ​ ​ | Value | ​ ​ ​ | Losses | ​ ​ ​ | Value | ​ ​ ​ | Losses
​ |  | (In Thousands)
AVAILABLE-FOR-SALE SECURITIES: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Agency mortgage-backed securities |  | $ | 20,762 | ​ | $ | (21) | ​ | $ | 236,437 | ​ | $ | (25,899) | ​ | $ | 257,199 | ​ | $ | (25,920)
Agency collateralized mortgage obligations | ​ | ​ | 9,098 | ​ | ​ | (95) | ​ | ​ | 60,041 | ​ | ​ | (5,835) | ​ | ​ | 69,139 | ​ | ​ | (5,930)
States and political subdivisions securities | ​ | ​ | 10,724 | ​ | ​ | (289) | ​ | ​ | 36,633 | ​ | ​ | (2,197) | ​ | ​ | 47,357 | ​ | ​ | (2,486)
Small Business Administration securities | ​ | ​ | 6,971 | ​ | ​ | (59) | ​ | ​ | 47,445 | ​ | ​ | (5,447) | ​ | ​ | 54,416 | ​ | ​ | (5,506)
​ |  | $ | 47,555 | ​ | $ | (464) | ​ | $ | 380,556 | ​ | $ | (39,378) | ​ | $ | 428,111 | ​ | $ | (39,842)
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
HELD-TO-MATURITY SECURITIES: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Agency mortgage-backed securities | ​ | $ | — | ​ | $ | — | ​ | $ | 64,736 | ​ | $ | (5,820) | ​ | $ | 64,736 | ​ | $ | (5,820)
Agency collateralized mortgage obligations | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 90,194 | ​ | ​ | (10,739) | ​ | ​ | 90,194 | ​ | ​ | (10,739)
States and political subdivisions securities | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 5,590 | ​ | ​ | (515) | ​ | ​ | 5,590 | ​ | ​ | (515)
​ | ​ | $ | — | ​ | $ | — | ​ | $ | 160,520 | ​ | $ | (17,074) | ​ | $ | 160,520 | ​ | $ | (17,074)
​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ ​ ​ | December 31, 2025
​ | ​ | Less than 12 Months | ​ | 12 Months or More | ​ | Total
​ | ​ | Fair | ​ | Unrealized | ​ | Fair | ​ | Unrealized | ​ | Fair | ​ | Unrealized
Description of Securities | ​ ​ ​ ​ | Value | ​ ​ ​ | Losses | ​ ​ ​ ​ | Value | ​ ​ ​ | Losses | ​ ​ ​ | Value | ​ ​ ​ | Losses
​ |  | (In Thousands)
AVAILABLE-FOR-SALE SECURITIES: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Agency mortgage-backed securities |  | $ | — |  | $ | — |  | $ | 241,503 |  | $ | (25,174) |  | $ | 241,503 |  | $ | (25,174)
Agency collateralized mortgage obligations | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 70,774 | ​ | ​ | (6,065) | ​ | ​ | 70,774 | ​ | ​ | (6,065)
States and political subdivisions securities | ​ | ​ | 4,409 | ​ | ​ | (109) | ​ | ​ | 43,528 | ​ | ​ | (1,929) | ​ | ​ | 47,937 | ​ | ​ | (2,038)
Small Business Administration securities | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 48,807 | ​ | ​ | (5,163) | ​ | ​ | 48,807 | ​ | ​ | (5,163)
​ |  | $ | 4,409 | ​ | $ | (109) |  | $ | 404,612 | ​ | $ | (38,331) |  | $ | 409,021 | ​ | $ | (38,440)
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
HELD-TO-MATURITY SECURITIES: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Agency mortgage-backed securities | ​ | $ | — | ​ | $ | — | ​ | $ | 65,332 | ​ | $ | (5,694) | ​ | $ | 65,332 | ​ | $ | (5,694)
Agency collateralized mortgage obligations | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 91,637 | ​ | ​ | (10,424) | ​ | ​ | 91,637 | ​ | ​ | (10,424)
States and political subdivisions securities | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 5,660 | ​ | ​ | (453) | ​ | ​ | 5,660 | ​ | ​ | (453)
​ | ​ | $ | — | ​ | $ | — | ​ | $ | 162,629 | ​ | $ | (16,571) | ​ | $ | 162,629 | ​ | $ | (16,571)
​

X
- Definition Tabular disclosure of information about investment in debt security measured at amortized cost (held-to-maturity) and fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References No definition available. + Details
Name: | gsbc_DebtSecuritiesHeldToMaturityAndAvailableForSaleSecuritiesTableTextBlock
Namespace Prefix: | gsbc_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 55 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479081/326-30-55-8 Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-6 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479106/326-30-50-4 + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionFairValueTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of maturities of an entity's investments as well as any other information pertinent to the investments. + References No definition available. + Details
Name: | us-gaap_InvestmentsClassifiedByContractualMaturityDateTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration