v3.25.4

Fair Value (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Sep. 30, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage loans held for sale	$ 14,488		$ 58,325
Net gain on the sale of loans	2,329	$ 1,115
Investment securities, available for sale	454,493		520,659
Real estate owned	1,975		1,921
Cost to dispose related to properties measured at fair value included in Consolidated Statements of Condition	$ 438		434
Derivatives, Determination of Fair Value	Derivatives qualifying as cash flow hedges are settled daily
Loans, net	$ 15,741,688		15,663,312
Interest Rate Swap | Cash Flow Hedge | Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0
Subject To Pending Agency Contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage loans held for sale	11,365		22,861
Net gain on the sale of loans	(110)	$ (57)
Unpaid principal balance	11,149		22,306
Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage loans held for sale	14,488		58,325
Investment securities, available for sale	454,493		520,659
Fair Value, Inputs, Level 2 | Valuation, Cost Approach
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage loans held for sale	3,075		34,801
Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage loans held for sale	0		0
Investment securities, available for sale	0		0
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage loans held for sale	11,365		22,861
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage loans held for sale	11,365		22,861
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Market Approach Valuation Technique | U.S. Government Obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities, available for sale	454,493		520,659
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage loans held for sale	0		0
Fair Value, Measurements, Nonrecurring | Fair Value, Inputs, Level 3 | Cost Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Real estate owned	2,413		2,355
Fair Value, Measurements, Nonrecurring | Fair Value, Inputs, Level 3 | Carried At Original Or Adjusted Cost Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Real estate owned	$ 0		$ 0

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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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The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

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Fair value as of the balance sheet date of interest rate derivative assets, net of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized on the balance sheet.

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Fair value portion of mortgage loans held-for-sale.

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