FAIR VALUE MEASUREMENTS - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Fair value of assets and liabilities
Investment securities available-for-sale	$ 410,624	$ 235,821
Equity securities	27,585	18,514
Recurring
Fair value of assets and liabilities
Equity securities	472
Loans held-for-sale	1,062	109,788
Recurring \| Level I
Fair value of assets and liabilities
Equity securities	472
Loans held-for-sale	0	0
Recurring \| Level II
Fair value of assets and liabilities
Equity securities	0
Loans held-for-sale	1,062	109,788
Recurring \| Level III
Fair value of assets and liabilities
Equity securities	0
Loans held-for-sale	0	0
United States government agency securities
Fair value of assets and liabilities
Investment securities available-for-sale	56,992	51,996
United States government agency securities \| Recurring
Fair value of assets and liabilities
Investment securities available-for-sale	56,992	51,996
United States government agency securities \| Recurring \| Level I
Fair value of assets and liabilities
Investment securities available-for-sale	0	0
United States government agency securities \| Recurring \| Level II
Fair value of assets and liabilities
Investment securities available-for-sale	56,992	51,996
United States government agency securities \| Recurring \| Level III
Fair value of assets and liabilities
Investment securities available-for-sale	0	0
United States sponsored mortgage-backed securities
Fair value of assets and liabilities
Investment securities available-for-sale	95,769	58,312
United States sponsored mortgage-backed securities \| Recurring
Fair value of assets and liabilities
Investment securities available-for-sale	95,769	58,312
United States sponsored mortgage-backed securities \| Recurring \| Level I
Fair value of assets and liabilities
Investment securities available-for-sale	0	0
United States sponsored mortgage-backed securities \| Recurring \| Level II
Fair value of assets and liabilities
Investment securities available-for-sale	95,769	58,312
United States sponsored mortgage-backed securities \| Recurring \| Level III
Fair value of assets and liabilities
Investment securities available-for-sale	0	0
Municipal securities \| Recurring
Fair value of assets and liabilities
Investment securities available-for-sale	231,887	113,092
Municipal securities \| Recurring \| Level I
Fair value of assets and liabilities
Investment securities available-for-sale	0	0
Municipal securities \| Recurring \| Level II
Fair value of assets and liabilities
Investment securities available-for-sale	188,208	75,833
Municipal securities \| Recurring \| Level III
Fair value of assets and liabilities
Investment securities available-for-sale	43,679	37,259
Other securities
Fair value of assets and liabilities
Investment securities available-for-sale	18,476	12,421
Other securities \| Recurring
Fair value of assets and liabilities
Investment securities available-for-sale	18,476	12,421
Other securities \| Recurring \| Level I
Fair value of assets and liabilities
Investment securities available-for-sale	0	0
Other securities \| Recurring \| Level II
Fair value of assets and liabilities
Investment securities available-for-sale	18,476	12,421
Other securities \| Recurring \| Level III
Fair value of assets and liabilities
Investment securities available-for-sale	0	0
Interest rate lock commitment \| Recurring
Fair value of assets and liabilities
Derivative asset		1,660
Interest rate lock commitment \| Recurring \| Level I
Fair value of assets and liabilities
Derivative asset		0
Interest rate lock commitment \| Recurring \| Level II
Fair value of assets and liabilities
Derivative asset		0
Interest rate lock commitment \| Recurring \| Level III
Fair value of assets and liabilities
Derivative asset		1,660
Interest rate swap \| Recurring
Fair value of assets and liabilities
Derivative asset	13,822	5,722
Derivative liability	13,822	5,722
Interest rate swap \| Recurring \| Level I
Fair value of assets and liabilities
Derivative asset	0	0
Derivative liability	0	0
Interest rate swap \| Recurring \| Level II
Fair value of assets and liabilities
Derivative asset	13,822	5,722
Derivative liability	13,822	5,722
Interest rate swap \| Recurring \| Level III
Fair value of assets and liabilities
Derivative asset	0	0
Derivative liability	0	0
Fair value hedge \| Recurring
Fair value of assets and liabilities
Derivative asset	2,215	1,770
Derivative liability	2,141	1,418
Fair value hedge \| Recurring \| Level I
Fair value of assets and liabilities
Derivative asset	0	0
Derivative liability	0	0
Fair value hedge \| Recurring \| Level II
Fair value of assets and liabilities
Derivative asset	2,215	1,770
Derivative liability	2,141	1,418
Fair value hedge \| Recurring \| Level III
Fair value of assets and liabilities
Derivative asset	0	0
Derivative liability	$ 0	0
Mortgage-backed security hedges \| Recurring
Fair value of assets and liabilities
Derivative liability		186
Mortgage-backed security hedges \| Recurring \| Level I
Fair value of assets and liabilities
Derivative liability		0
Mortgage-backed security hedges \| Recurring \| Level II
Fair value of assets and liabilities
Derivative liability		186
Mortgage-backed security hedges \| Recurring \| Level III
Fair value of assets and liabilities
Derivative liability		$ 0

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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