LOANS HELD FOR INVESTMENT, NET - Credit Quality Indicators (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Credit Risk Profile of Real Estate Loans [Abstract]
Total Loans	$ 10,876,415		$ 10,876,415		$ 10,566,831
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
YTD Gross Charge-Offs 2022/2021					477
YTD Gross Charge-Offs 2021/2020					4,720
YTD Gross Charge-Offs 2020/2019			38		2,088
YTD Gross Charge-Offs 2018 and Prior/2017 and Prior			1,991		2,414
YTD Gross Charge-Offs Revolving			434		1,460
YTD Gross Charge-Offs Revolving-Term			3,325		242
YTD Gross Charge-Offs			5,788		11,401
Pass
Credit Risk Profile of Real Estate Loans [Abstract]
2023/2022	665,472		665,472
2022/2021	2,815,208		2,815,208		2,845,428
2021/2020	1,714,236		1,714,236		1,733,872
2020/2019	1,027,566		1,027,566		1,196,053
2019/2018	996,552		996,552		1,024,753
2018/2017 and Prior	2,497,638		2,497,638		522,005
2016 and Prior					2,175,148
Revolving	703,259		703,259		726,712
Revolving-Term	68,607		68,607		59,849
Total Loans	10,488,538		10,488,538		10,283,820
Special Mention
Credit Risk Profile of Real Estate Loans [Abstract]
2023/2022	528		528
2022/2021	3,284		3,284		6,634
2021/2020	5,562		5,562
2020/2019	97,943		97,943		20,549
2019/2018	20,013		20,013		17,364
2018/2017 and Prior	54,607		54,607		16,628
2016 and Prior					31,664
Revolving	11,008		11,008		9,641
Revolving-Term	9,661		9,661		1,204
Total Loans	202,606		202,606		103,684
Substandard
Credit Risk Profile of Real Estate Loans [Abstract]
2023/2022	52		52
2022/2021	898		898		5,242
2021/2020	1,068		1,068		2,052
2020/2019	45,821		45,821		23,233
2019/2018	11,155		11,155		19,143
2018/2017 and Prior	94,248		94,248		22,819
2016 and Prior					66,232
Revolving	8,637		8,637		11,290
Revolving-Term	8,096		8,096		10,505
Total Loans	169,975		169,975		160,516
Doubtful
Credit Risk Profile of Real Estate Loans [Abstract]
2019/2018	8,332		8,332		8,332
2018/2017 and Prior	807		807		752
2016 and Prior					2,048
Total Loans	9,139		9,139		11,132
Excludes Other Loans
Credit Risk Profile of Real Estate Loans [Abstract]
2023/2022	666,052		666,052
2022/2021	2,819,390		2,819,390		2,857,304
2021/2020	1,720,866		1,720,866		1,735,924
2020/2019	1,171,330		1,171,330		1,239,835
2019/2018	1,036,052		1,036,052		1,069,592
2018/2017 and Prior	2,647,300		2,647,300		562,204
2016 and Prior					2,275,092
Revolving	722,904		722,904		747,643
Revolving-Term	86,364		86,364		71,558
Total Loans	10,870,258		10,870,258		10,559,152
Business Loan Portfolio Segment [Member]
Credit Risk Profile of Real Estate Loans [Abstract]
2023/2022	150,477		150,477
2022/2021	448,062		448,062		461,575
2021/2020	218,135		218,135		229,523
2020/2019	185,074		185,074		197,259
2019/2018	173,944		173,944		188,094
2018/2017 and Prior	369,852		369,852		149,322
2016 and Prior					261,330
Revolving	645,850		645,850		671,312
Revolving-Term	58,714		58,714		53,442
Total Loans	2,250,108		2,250,108		2,211,857
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
YTD Gross Charge-Offs 2022/2021					477
YTD Gross Charge-Offs 2021/2020					4,720
YTD Gross Charge-Offs 2020/2019			38		2,088
YTD Gross Charge-Offs 2018 and Prior/2017 and Prior			1,991		2,414
YTD Gross Charge-Offs Revolving			434		1,460
YTD Gross Charge-Offs Revolving-Term			3,311		242
YTD Gross Charge-Offs	3,745	$ 645	5,774	$ 3,280	11,401
Business Loan Portfolio Segment [Member] | Pass
Credit Risk Profile of Real Estate Loans [Abstract]
2023/2022	149,897		149,897
2022/2021	443,880		443,880		449,699
2021/2020	216,423		216,423		228,143
2020/2019	175,305		175,305		187,522
2019/2018	160,702		160,702		173,527
2018/2017 and Prior	325,188		325,188		130,576
2016 and Prior					240,131
Revolving	626,364		626,364		650,960
Revolving-Term	42,465		42,465		43,552
Total Loans	2,140,224		2,140,224		2,104,110
Business Loan Portfolio Segment [Member] | Special Mention
Credit Risk Profile of Real Estate Loans [Abstract]
2023/2022	528		528
2022/2021	3,284		3,284		6,634
2021/2020	1,316		1,316
2020/2019	1,430		1,430		894
2019/2018	1,317		1,317		1,529
2018/2017 and Prior	13,447		13,447		15,893
2016 and Prior					4,213
Revolving	10,849		10,849		9,062
Revolving-Term	8,946		8,946		478
Total Loans	41,117		41,117		38,703
Business Loan Portfolio Segment [Member] | Substandard
Credit Risk Profile of Real Estate Loans [Abstract]
2023/2022	52		52
2022/2021	898		898		5,242
2021/2020	396		396		1,380
2020/2019	8,339		8,339		8,843
2019/2018	3,593		3,593		4,706
2018/2017 and Prior	30,410		30,410		2,101
2016 and Prior					14,938
Revolving	8,637		8,637		11,290
Revolving-Term	7,303		7,303		9,412
Total Loans	59,628		59,628		57,912
Business Loan Portfolio Segment [Member] | Doubtful
Credit Risk Profile of Real Estate Loans [Abstract]
2019/2018	8,332		8,332		8,332
2018/2017 and Prior	807		807		752
2016 and Prior					2,048
Total Loans	9,139		9,139		11,132
One-to-four family residential and cooperative/condominium apartment
Credit Risk Profile of Real Estate Loans [Abstract]
2023/2022	112,062		112,062
2022/2021	221,019		221,019		225,031
2021/2020	104,481		104,481		108,185
2020/2019	72,312		72,312		73,758
2019/2018	65,299		65,299		66,742
2018/2017 and Prior	232,127		232,127		67,180
2016 and Prior					176,292
Revolving	33,785		33,785		41,751
Revolving-Term	14,895		14,895		14,382
Total Loans	855,980		855,980		773,321
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
YTD Gross Charge-Offs Revolving-Term			14
YTD Gross Charge-Offs	14		14
One-to-four family residential and cooperative/condominium apartment | Pass
Credit Risk Profile of Real Estate Loans [Abstract]
2023/2022	112,062		112,062
2022/2021	221,019		221,019		225,031
2021/2020	104,481		104,481		108,185
2020/2019	71,297		71,297		72,732
2019/2018	64,080		64,080		65,515
2018/2017 and Prior	219,848		219,848		66,038
2016 and Prior					164,338
Revolving	33,626		33,626		41,172
Revolving-Term	13,387		13,387		12,563
Total Loans	839,800		839,800		755,574
One-to-four family residential and cooperative/condominium apartment | Special Mention
Credit Risk Profile of Real Estate Loans [Abstract]
2018/2017 and Prior	761		761		735
2016 and Prior					1,175
Revolving	159		159		579
Revolving-Term	715		715		726
Total Loans	1,635		1,635		3,215
One-to-four family residential and cooperative/condominium apartment | Substandard
Credit Risk Profile of Real Estate Loans [Abstract]
2020/2019	1,015		1,015		1,026
2019/2018	1,219		1,219		1,227
2018/2017 and Prior	11,518		11,518		407
2016 and Prior					10,779
Revolving-Term	793		793		1,093
Total Loans	14,545		14,545		14,532
Multifamily residential and residential mixed-use
Credit Risk Profile of Real Estate Loans [Abstract]
2023/2022	209,997		209,997
2022/2021	1,372,631		1,372,631		1,386,549
2021/2020	598,163		598,163		582,393
2020/2019	321,703		321,703		328,718
2019/2018	409,088		409,088		414,117
2018/2017 and Prior	1,204,082		1,204,082		147,385
2016 and Prior					1,155,080
Revolving	12,229		12,229		12,584
Revolving-Term	4,465		4,465
Total Loans	4,132,358		4,132,358		4,026,826
Multifamily residential and residential mixed-use | Pass
Credit Risk Profile of Real Estate Loans [Abstract]
2023/2022	209,997		209,997
2022/2021	1,372,631		1,372,631		1,386,549
2021/2020	593,917		593,917		582,393
2020/2019	292,798		292,798		316,424
2019/2018	395,000		395,000		395,933
2018/2017 and Prior	1,128,010		1,128,010		127,074
2016 and Prior					1,107,281
Revolving	12,229		12,229		12,584
Revolving-Term	4,465		4,465
Total Loans	4,009,047		4,009,047		3,928,238
Multifamily residential and residential mixed-use | Special Mention
Credit Risk Profile of Real Estate Loans [Abstract]
2021/2020	4,246		4,246
2020/2019	18,194		18,194
2019/2018	14,088		14,088		11,183
2018/2017 and Prior	30,723		30,723
2016 and Prior					14,168
Total Loans	67,251		67,251		25,351
Multifamily residential and residential mixed-use | Substandard
Credit Risk Profile of Real Estate Loans [Abstract]
2020/2019	10,711		10,711		12,294
2019/2018					7,001
2018/2017 and Prior	45,349		45,349		20,311
2016 and Prior					33,631
Total Loans	56,060		56,060		73,237
Non-owner Occupied Commercial Real Estate Portfolio Segment [Member]
Credit Risk Profile of Real Estate Loans [Abstract]
2023/2022	193,516		193,516
2022/2021	730,726		730,726		747,272
2021/2020	665,034		665,034		662,623
2020/2019	584,594		584,594		628,858
2019/2018	372,003		372,003		384,696
2018/2017 and Prior	840,687		840,687		198,317
2016 and Prior					680,303
Revolving	11,632		11,632		11,963
Revolving-Term	8,040		8,040		3,453
Total Loans	3,406,232		3,406,232		3,317,485
Non-owner Occupied Commercial Real Estate Portfolio Segment [Member] | Pass
Credit Risk Profile of Real Estate Loans [Abstract]
2023/2022	193,516		193,516
2022/2021	730,726		730,726		747,272
2021/2020	665,019		665,019		662,608
2020/2019	480,519		480,519		608,133
2019/2018	361,052		361,052		373,835
2018/2017 and Prior	824,040		824,040		198,317
2016 and Prior					661,311
Revolving	11,632		11,632		11,963
Revolving-Term	8,040		8,040		3,453
Total Loans	3,274,544		3,274,544		3,266,892
Non-owner Occupied Commercial Real Estate Portfolio Segment [Member] | Special Mention
Credit Risk Profile of Real Estate Loans [Abstract]
2020/2019	78,319		78,319		19,655
2019/2018	4,608		4,608		4,652
2018/2017 and Prior	9,676		9,676
2016 and Prior					12,108
Total Loans	92,603		92,603		36,415
Non-owner Occupied Commercial Real Estate Portfolio Segment [Member] | Substandard
Credit Risk Profile of Real Estate Loans [Abstract]
2021/2020	15		15		15
2020/2019	25,756		25,756		1,070
2019/2018	6,343		6,343		6,209
2018/2017 and Prior	6,971		6,971
2016 and Prior					6,884
Total Loans	39,085		39,085		14,178
Non-owner Occupied Commercial Real Estate Portfolio Segment [Member] | Total real estate loans
Credit Risk Profile of Real Estate Loans [Abstract]
Total Loans	3,406,232		3,406,232		3,317,485
Acquisition, development, and construction ("ADC")
Credit Risk Profile of Real Estate Loans [Abstract]
2022/2021	46,952		46,952		36,877
2021/2020	135,053		135,053		153,200
2020/2019	7,647		7,647		11,242
2019/2018	15,718		15,718		15,943
2018/2017 and Prior	552		552
2016 and Prior					2,087
Revolving	19,408		19,408		10,033
Revolving-Term	250		250		281
Total Loans	225,580		225,580		229,663
Acquisition, development, and construction ("ADC") | Pass
Credit Risk Profile of Real Estate Loans [Abstract]
2022/2021	46,952		46,952		36,877
2021/2020	134,396		134,396		152,543
2020/2019	7,647		7,647		11,242
2019/2018	15,718		15,718		15,943
2018/2017 and Prior	552		552
2016 and Prior					2,087
Revolving	19,408		19,408		10,033
Revolving-Term	250		250		281
Total Loans	224,923		224,923		229,006
Acquisition, development, and construction ("ADC") | Substandard
Credit Risk Profile of Real Estate Loans [Abstract]
2021/2020	657		657		657
Total Loans	657		657		657
Other Loans
Credit Risk Profile of Real Estate Loans [Abstract]
Total Loans	6,157		6,157		7,679
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
YTD Gross Charge-Offs	33		34	$ 3
Other Loans | Credit Risk Profile
Credit Risk Profile of Real Estate Loans [Abstract]
Total Loans	6,157		6,157
Other Loans | Performing
Credit Risk Profile of Real Estate Loans [Abstract]
Total Loans					7,580
Other Loans | Performing | Credit Risk Profile
Credit Risk Profile of Real Estate Loans [Abstract]
Total Loans	5,937		5,937
Other Loans | Non-Accrual
Credit Risk Profile of Real Estate Loans [Abstract]
Total Loans					$ 99
Other Loans | Non-Accrual | Credit Risk Profile
Credit Risk Profile of Real Estate Loans [Abstract]
Total Loans	$ 220		$ 220