LOANS HELD FOR INVESTMENT, NET - Allowance for Credit Losses Activity (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Allowance for credit losses:
Allowance for credit losses, Beginning balance			$ 71,743
Provision (recovery) for credit losses	$ 11,603	$ 1,806	22,398	$ (950)
Allowance for credit losses, Ending balance	85,221		85,221		$ 71,743
Non-accrual with No Allowance	24,265		24,265		3,780
Non-accrual with Allowance	25,198		25,198		25,319
Reserve	20,027		20,027		14,202
Interest income on non-accrual loans held for investment
Interest income on non-accrual loans	0	0	0	0
Business Loans
Allowance for credit losses:
Allowance for credit losses, Beginning balance	37,115	39,700	35,962	47,029	47,029
Provision (recovery) for credit losses	10,710	1,822	13,656	(328)
Charge-offs	(3,090)	(5,147)	(5,065)	(10,921)	(15,364)
Recoveries	291	305	473	900
Allowance for credit losses, Ending balance	45,026	36,680	45,026	36,680	35,962
Non-accrual with No Allowance	4,771		4,771		1,482
Non-accrual with Allowance	20,640		20,640		13,185
Reserve	19,683		19,683		12,932
One-to-Four Family Residential and Cooperative/Condominium Apartment
Allowance for credit losses:
Allowance for credit losses, Beginning balance	7,305	6,419	6,813	5,969	5,969
Provision (recovery) for credit losses	1,341	787	1,833	1,251
Charge-offs				(14)	(14)
Allowance for credit losses, Ending balance	8,646	7,206	8,646	7,206	6,813
Non-accrual with Allowance	3,880		3,880		3,248
Reserve	36		36		133
Multifamily Residential and Residential Mixed-Use
Allowance for credit losses:
Allowance for credit losses, Beginning balance	12,357	8,190	7,237	8,360	8,360
Provision (recovery) for credit losses	1,439	(621)	9,110	(791)
Charge-offs	(1,294)	(2)	(3,845)	(2)	(2)
Recoveries	1		1
Allowance for credit losses, Ending balance	12,503	7,567	12,503	7,567	7,237
Non-Owner-Occupied Commercial Real Estate
Allowance for credit losses:
Allowance for credit losses, Beginning balance	18,340	18,440	19,623	20,153	20,153
Provision (recovery) for credit losses	(1,942)	(10)	(3,225)	(1,723)
Charge-offs	(96)		(96)
Allowance for credit losses, Ending balance	16,302	18,430	16,302	18,430	19,623
Non-accrual with No Allowance	19,494		19,494		2,298
Non-accrual with Allowance	15		15		8,229
Reserve	15		15		832
Acquisition, development, and construction ("ADC")
Allowance for credit losses:
Allowance for credit losses, Beginning balance	2,455	2,558	1,989	1,723	1,723
Provision (recovery) for credit losses	66	(220)	532	615
Allowance for credit losses, Ending balance	2,521	2,338	2,521	2,338	1,989
Non-accrual with Allowance	657		657		657
Reserve	287		287		305
Other Loans
Allowance for credit losses:
Allowance for credit losses, Beginning balance	240	339	119	273	273
Provision (recovery) for credit losses	(6)	23	150	116
Charge-offs	(14)	(26)	(59)	(60)
Recoveries	3	6	13	13
Allowance for credit losses, Ending balance	223	342	223	342	119
Non-accrual with Allowance	6		6
Reserve	6		6
Total (includes other loans)
Allowance for credit losses:
Allowance for credit losses, Beginning balance	77,812	75,646	71,743	83,507	83,507
Provision (recovery) for credit losses	11,608	1,781	22,056	(860)
Charge-offs	(4,494)	(5,175)	(9,065)	(10,997)
Recoveries	295	311	487	913
Allowance for credit losses, Ending balance	$ 85,221	$ 72,563	$ 85,221	$ 72,563	$ 71,743