FAIR VALUE - Summary of assets measured at level 3 fair value on recurring basis (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Summary of assets measured on a recurring and nonrecurring basis
Available-for-sale securities, at fair value	$ 36,666	$ 58,903
Other real estate owned valuation allowance	1,900	1,700
Impaired Financing Receivable, with Related Allowance, Recorded Investment	3,421	4,412
Loans and Leases Receivable, Allowance	12,539	7,875
Bank charged off		200
Other real estate owned, gross	2,100	2,400
Other real estate owned	194	658
Net recorded investment	1,958	11,437
U.S. Treasury debt
Summary of assets measured on a recurring and nonrecurring basis
Available-for-sale securities, at fair value	254	254
Recurring
Summary of assets measured on a recurring and nonrecurring basis
Available-for-sale securities, at fair value	36,666	58,903
Equity securities	730	713
Guarantee asset	232
Recurring | U.S. Treasury debt
Summary of assets measured on a recurring and nonrecurring basis
Available-for-sale securities, at fair value	254	254
Recurring | Corporate collateralized mortgage obligations and mortgage-backed securities
Summary of assets measured on a recurring and nonrecurring basis
Available-for-sale securities, at fair value	4,087	10,420
Recurring | IRLC and FSC, net
Summary of assets measured on a recurring and nonrecurring basis
Derivative asset, Fair value	9,752	1,184
Recurring | GNMA
Summary of assets measured on a recurring and nonrecurring basis
Available-for-sale securities, at fair value	24,604	45,312
Recurring | FNMA
Summary of assets measured on a recurring and nonrecurring basis
Available-for-sale securities, at fair value	1,677	2,917
Nonrecurring
Summary of assets measured on a recurring and nonrecurring basis
Other real estate owned		658
Level 1 | Recurring
Summary of assets measured on a recurring and nonrecurring basis
Available-for-sale securities, at fair value	254	254
Equity securities	730	713
Level 1 | Recurring | U.S. Treasury debt
Summary of assets measured on a recurring and nonrecurring basis
Available-for-sale securities, at fair value	254	254
Level 2 | Recurring
Summary of assets measured on a recurring and nonrecurring basis
Available-for-sale securities, at fair value	36,412	58,649
Level 2 | Recurring | Corporate collateralized mortgage obligations and mortgage-backed securities
Summary of assets measured on a recurring and nonrecurring basis
Available-for-sale securities, at fair value	4,087	10,420
Level 2 | Recurring | GNMA
Summary of assets measured on a recurring and nonrecurring basis
Available-for-sale securities, at fair value	24,604	45,312
Level 2 | Recurring | FNMA
Summary of assets measured on a recurring and nonrecurring basis
Available-for-sale securities, at fair value	1,677	2,917
Level 3
Summary of assets measured on a recurring and nonrecurring basis
Impaired Financing Receivable, with Related Allowance, Recorded Investment	3,400	4,400
Loans and Leases Receivable, Allowance	1,600	800
Provision for loan losses	1,600	800
Level 3 | Recurring
Summary of assets measured on a recurring and nonrecurring basis
Guarantee asset	232
Level 3 | Recurring | IRLC and FSC, net
Summary of assets measured on a recurring and nonrecurring basis
Derivative asset, Fair value	9,752	1,184
Level 3 | Nonrecurring
Summary of assets measured on a recurring and nonrecurring basis
Other real estate owned		658
Commercial properties | Nonrecurring
Summary of assets measured on a recurring and nonrecurring basis
Other real estate owned	194
Commercial properties | Level 3 | Nonrecurring
Summary of assets measured on a recurring and nonrecurring basis
Other real estate owned	194
Commercial and Industrial | Nonrecurring
Summary of assets measured on a recurring and nonrecurring basis
Net recorded investment	1,800	3,579
Commercial and Industrial | Level 3 | Nonrecurring
Summary of assets measured on a recurring and nonrecurring basis
Net recorded investment	$ 1,800	$ 3,579