Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
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FAIR VALUE MEASUREMENTS - Fair value of assets measured on a recurring basis (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022	Dec. 31, 2021
Assets
Mortgage servicing rights	$ 13,733	$ 9,582	$ 5,016
Recurring
Assets
Mortgage servicing rights	13,733	9,582
Recurring \| U.S. Treasury securities
Assets
Securities available for sale	41,835	142,097
Recurring \| Obligations of U.S. Government sponsored agencies
Assets
Securities available for sale	27,780	21,749
Recurring \| Obligations of states and political subdivisions
Assets
Securities available for sale	54,121	83,186
Recurring \| Mortgage-backed securities
Assets
Securities available for sale	35,840	36,637
Recurring \| Corporate notes
Assets
Securities available for sale	18,738	19,994
Recurring \| Certificates of deposit
Assets
Securities available for sale	732	974
Recurring \| Level 2
Assets
Mortgage servicing rights	13,733	9,582
Recurring \| Level 2 \| U.S. Treasury securities
Assets
Securities available for sale	41,835	142,097
Recurring \| Level 2 \| Obligations of U.S. Government sponsored agencies
Assets
Securities available for sale	27,780	21,749
Recurring \| Level 2 \| Obligations of states and political subdivisions
Assets
Securities available for sale	54,121	83,186
Recurring \| Level 2 \| Mortgage-backed securities
Assets
Securities available for sale	35,840	36,637
Recurring \| Level 2 \| Corporate notes
Assets
Securities available for sale	18,738	19,994
Recurring \| Level 2 \| Certificates of deposit
Assets
Securities available for sale	732	974
Recurring \| Level 3
Assets
Assets at fair value	$ 0	$ 0