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Loans Receivable, Net - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended
Loans Receivable, Net - Narrative (Details) - USD ($)	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for credit losses	$ 18,009,000	$ 5,066,000	$ 24,163,000	$ 14,157,000
Interest reversed on non-accrual loans			715,000	25,000
Modified, commitment to lend	1,350,000		1,350,000		$ 462,000
Consumer mortgage loans secured by residential real estate properties for which formal foreclosure proceedings are in process	1,220,000		1,220,000		207,000
Residential real estate
Financing Receivable, Allowance for Credit Losses [Line Items]
OREO secured by residential real estate	0		0		$ 0
Other commercial
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for credit losses	2,869,000	1,081,000	4,591,000	3,374,000
Other commercial \| Payment Deferral
Financing Receivable, Allowance for Credit Losses [Line Items]
Modified in period, amount			136,000
Commercial real estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for credit losses	$ 11,865,000	1,582,000	13,333,000	5,789,000
Commercial real estate \| Payment Deferral
Financing Receivable, Allowance for Credit Losses [Line Items]
Modified in period, amount		$ 0	1,082,000
Bank of Idaho
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for credit losses			$ 14,594,000
Wheatland and RMB
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for credit losses				$ 5,271,000