Percentage of consolidated stockholders equity exceeding which no borrower had outstanding loans or commitments.

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Amount of writeoff of accrued interest on financing receivable recognized by reversing interest income.

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Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

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Amount, excluding accrued interest, of allowance for credit loss at acquisition date of financing receivable purchased with credit deterioration. Excludes net investment in lease.

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Amortized cost of financing receivable modified during period for debtor experiencing financial difficulty.

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Amount of commitment to lend additional funds to debtor experiencing financial difficulty for which creditor has modified terms of financing receivable.

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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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The cash outflow for a loan, supported by a promissory note, granted to related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth.

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Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure.

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Loans Receivable, Net - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivable, net	$ 17,055,808	$ 16,005,325
Percentage of consolidated stockholders equity exceeding which no borrower had outstanding loans or commitments	10.00%
Provision for credit losses	$ 27,179	20,790	$ 17,433
ACL on PCD loans acquired	3
Nonaccrual interest income reversed	351	356	1,175
Financing receivable, modified, commitment to lend	462	5,361
Consumer mortgage loans secured by residential real estate properties for which formal foreclosure proceedings are in process	207	98
Related Party
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivable, net	110,150	110,707
Origination of notes receivable from related parties	15,140
Repayment of notes receivable from related parties	15,697
Asset Pledged as Collateral
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivable, net	11,827,421
Wheatland and RMB
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for credit losses	8,072
Residential Real Estate
Financing Receivable, Allowance for Credit Losses [Line Items]
OREO secured by residential real estate	0	15
Commercial Real Estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for credit losses	10,446	6,748	7,231
ACL on PCD loans acquired	3
Commercial Real Estate \| Payment Deferral
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans modified in period	183	2,159
Other Commercial
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for credit losses	7,162	$ 1,996	$ (704)
ACL on PCD loans acquired	0
Other Commercial \| Payment Deferral
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans modified in period	$ 37