LOANS RECEIVABLE AND ALLOWANCE FOR CREDIT LOSSES ON LOANS - Aging Analysis of Past Due Loans (Details) $ in Thousands	Dec. 31, 2022 USD ($) loan	Dec. 31, 2021 USD ($) loan	Dec. 31, 2020 USD ($)
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	$ 2,218,852	$ 1,754,175	$ 1,571,153
Non-Accrual	$ 8,652
Number of TDRs which incurred payment default | loan	0
REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	$ 1,421,260	1,090,303	923,541
Non-Accrual	966
CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	569,572	422,043	374,153
Non-Accrual	1,352
COMMERCIAL BUSINESS LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	228,020	241,829	$ 273,459
Non-Accrual	3,700	0
Commercial | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	334,059	264,429
Construction and development | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	342,591	240,553
Home equity. | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	55,387	41,017
Non-Accrual	46
One-to-four-family | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	469,485	366,146
Non-Accrual	920
Multi-family | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	219,738	178,158
Indirect home improvement | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	495,941	336,285
Non-Accrual	1,076
Marine | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	70,567	82,778
Non-Accrual	267
Other consumer loans | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	3,064	2,980
Non-Accrual	9
Commercial and industrial | COMMERCIAL BUSINESS LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	196,791	208,552
Non-Accrual	6,334
Warehouse lending | COMMERCIAL BUSINESS LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	31,229	33,277
30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	3,010	2,561
30-59 Days Past Due | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	29	593
30-59 Days Past Due | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	2,980	1,177
30-59 Days Past Due | COMMERCIAL BUSINESS LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	1	791
30-59 Days Past Due | Commercial | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	0	0
30-59 Days Past Due | Construction and development | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	0	0
30-59 Days Past Due | Home equity. | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	29	0
30-59 Days Past Due | One-to-four-family | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	0	593
30-59 Days Past Due | Multi-family | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	0	0
30-59 Days Past Due | Indirect home improvement | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	2,298	1,047
30-59 Days Past Due | Marine | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	650	119
30-59 Days Past Due | Other consumer loans | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	32	11
30-59 Days Past Due | Commercial and industrial | COMMERCIAL BUSINESS LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	1	791
30-59 Days Past Due | Warehouse lending | COMMERCIAL BUSINESS LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	0	0
60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	1,211	546
60-89 Days Past Due | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	104	264
60-89 Days Past Due | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	1,107	282
60-89 Days Past Due | COMMERCIAL BUSINESS LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	0	0
60-89 Days Past Due | Commercial | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	0	0
60-89 Days Past Due | Construction and development | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	0	0
60-89 Days Past Due | Home equity. | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	104	0
60-89 Days Past Due | One-to-four-family | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	0	264
60-89 Days Past Due | Multi-family | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	0	0
60-89 Days Past Due | Indirect home improvement | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	685	280
60-89 Days Past Due | Marine | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	385	0
60-89 Days Past Due | Other consumer loans | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	37	2
60-89 Days Past Due | Commercial and industrial | COMMERCIAL BUSINESS LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	0	0
60-89 Days Past Due | Warehouse lending | COMMERCIAL BUSINESS LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	0	0
90 Days or More Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	$ 3,719	$ 972
Number Of Loans Accruing Interest | loan	0	0
90 Days or More Past Due | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	$ 479	$ 659
90 Days or More Past Due | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	623	313
90 Days or More Past Due | COMMERCIAL BUSINESS LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	2,617	0
90 Days or More Past Due | Commercial | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	0	0
90 Days or More Past Due | Construction and development | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	0	0
90 Days or More Past Due | Home equity. | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	16	179
90 Days or More Past Due | One-to-four-family | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	463	480
90 Days or More Past Due | Multi-family | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	0	0
90 Days or More Past Due | Indirect home improvement | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	532	295
90 Days or More Past Due | Marine | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	86	0
90 Days or More Past Due | Other consumer loans | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	5	18
90 Days or More Past Due | Commercial and industrial | COMMERCIAL BUSINESS LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	2,617	0
90 Days or More Past Due | Warehouse lending | COMMERCIAL BUSINESS LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	0	0
Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	7,940	4,079
Past Due | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	612	1,516
Past Due | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	4,710	1,772
Past Due | COMMERCIAL BUSINESS LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	2,618	791
Past Due | Commercial | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	0	0
Past Due | Construction and development | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	0	0
Past Due | Home equity. | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	149	179
Past Due | One-to-four-family | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	463	1,337
Past Due | Multi-family | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	0	0
Past Due | Indirect home improvement | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	3,515	1,622
Past Due | Marine | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	1,121	119
Past Due | Other consumer loans | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	74	31
Past Due | Commercial and industrial | COMMERCIAL BUSINESS LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	2,618	791
Past Due | Warehouse lending | COMMERCIAL BUSINESS LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	0	0
Not Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	2,210,912	1,750,096
Not Past Due | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	1,420,648	1,088,787
Not Past Due | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	564,862	420,271
Not Past Due | COMMERCIAL BUSINESS LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	225,402	241,038
Not Past Due | Commercial | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	334,059	264,429
Not Past Due | Construction and development | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	342,591	240,553
Not Past Due | Home equity. | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	55,238	40,838
Not Past Due | One-to-four-family | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	469,022	364,809
Not Past Due | Multi-family | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	219,738	178,158
Not Past Due | Indirect home improvement | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	492,426	334,663
Not Past Due | Marine | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	69,446	82,659
Not Past Due | Other consumer loans | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	2,990	2,949
Not Past Due | Commercial and industrial | COMMERCIAL BUSINESS LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	194,173	207,761
Not Past Due | Warehouse lending | COMMERCIAL BUSINESS LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans receivable	31,229	33,277
Non-Accrual
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual	8,652	5,829
Non-Accrual | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual	966	781
Non-Accrual | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual	1,352	629
Non-Accrual | COMMERCIAL BUSINESS LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual	6,334	4,419
Non-Accrual | Commercial | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual	0	0
Non-Accrual | Construction and development | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual	0	0
Non-Accrual | Home equity. | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual	46	301
Non-Accrual | One-to-four-family | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual	920	480
Non-Accrual | Multi-family | REAL ESTATE LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual	0	0
Non-Accrual | Indirect home improvement | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual	1,076	554
Non-Accrual | Marine | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual	267	57
Non-Accrual | Other consumer loans | CONSUMER LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual	9	18
Non-Accrual | Commercial and industrial | COMMERCIAL BUSINESS LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual	6,334	4,419
Non-Accrual | Warehouse lending | COMMERCIAL BUSINESS LOANS
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual	$ 0	$ 0