Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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LOANS RECEIVABLE AND THE ALLOWANCE FOR CREDIT LOSSES (Allowance for Loan Losses) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2024
Financing Receivable, Allowance for Loan Losses [Roll Forward]
Provision for credit losses	$ (1,598)	$ (4,201)	$ (2,890)	$ (8,750)
Recoveries	476	641	729	1,572
Charge-offs	(577)	(1,664)	(2,046)	(5,342)
Financing Receivable, Allowance for Credit Loss	161,849	160,501	161,849	160,501	$ 160,276	$ 160,352	$ 157,323	$ 155,521
Commercial Real Estate
Financing Receivable, Allowance for Loan Losses [Roll Forward]
Provision for credit losses	(367)	(907)	(545)	96
Recoveries	12	53	23	110
Charge-offs	0	0	0	0
Financing Receivable, Allowance for Credit Loss	42,167	41,036	42,167	41,036	41,599	41,788	40,076	40,830
Multifamily Real Estate
Financing Receivable, Allowance for Loan Losses [Roll Forward]
Provision for credit losses	658	191	54	390
Recoveries	0	0	0	0
Charge-offs	0	0	0	0	0
Financing Receivable, Allowance for Credit Loss	9,859	9,918	9,859	9,918	9,805	9,201	10,109	10,308
Construction and Land
Financing Receivable, Allowance for Loan Losses [Roll Forward]
Provision for credit losses	2,470	2,082	3,393	(5,086)
Recoveries	5	0	9	0
Charge-offs	0	0	0	0
Financing Receivable, Allowance for Credit Loss	32,124	34,124	32,124	34,124	35,508	34,589	32,042	29,038
Commercial Business and Small Business Scored
Financing Receivable, Allowance for Loan Losses [Roll Forward]
Provision for credit losses	1,784	(457)	(4,233)	(3,255)
Recoveries	171	361	252	918
Charge-offs	(293)	(892)	(1,156)	(4,193)
Financing Receivable, Allowance for Credit Loss	41,114	38,591	41,114	38,591	37,785	39,452	38,665	38,611
Agricultural Business
Financing Receivable, Allowance for Loan Losses [Roll Forward]
Provision for credit losses	(720)	(936)	(79)	(840)
Recoveries	213	1	217	11
Charge-offs	(4)	(362)	(4)	(362)	(2,416)
Financing Receivable, Allowance for Credit Loss	5,859	6,216	5,859	6,216	5,567	4,930	5,641	5,727
One- to Four-Family Residential
Financing Receivable, Allowance for Loan Losses [Roll Forward]
Provision for credit losses	(174)	107	(99)	123
Recoveries	12	58	25	246
Charge-offs	0	0	0	(13)	(13)
Financing Receivable, Allowance for Credit Loss	19,478	20,917	19,478	20,917	19,552	19,640	20,752	20,807
Consumer Loan [Member]
Financing Receivable, Allowance for Loan Losses [Roll Forward]
Provision for credit losses	(713)	97	(1,471)	14
Recoveries	63	168	203	287
Charge-offs	(280)	(410)	(886)	(774)	(1,619)
Financing Receivable, Allowance for Credit Loss	$ 11,248	$ 9,699	11,248	$ 9,699	10,460	$ 10,752	$ 10,038	$ 10,200
Commercial Business
Financing Receivable, Allowance for Loan Losses [Roll Forward]
Charge-offs			$ (436)		$ (3,598)