Washington Federal (WAFD) 10-Q 3 Feb 23 2023 Q1 Quarterly report Financial data

Cover Page

Cover Page - shares	3 Months Ended
	Dec. 31, 2022	Jan. 31, 2023
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Dec. 31, 2022
Document Transition Report	false
Entity File Number	001-34654
Entity Registrant Name	WASHINGTON FEDERAL INC
Entity Incorporation, State or Country Code	WA
Entity Tax Identification Number	91-1661606
Entity Address, Address Line One	425 Pike Street
Entity Address, City or Town	Seattle
Entity Address, State or Province	WA
Entity Address, Postal Zip Code	98101
City Area Code	206
Local Phone Number	624-7930
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		65,415,338
Amendment Flag	false
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q1
Entity Central Index Key	0000936528
Current Fiscal Year End Date	--09-30
Common Stock, $1.00 par value per share
Document Information [Line Items]
Title of 12(b) Security	Common Stock, $1.00 par value per share
Trading Symbol	WAFD
Security Exchange Name	NASDAQ
Depositary Shares, Each Representing a 1/40th Interest in a Share of 4.875% Fixed Rate Series A Non-Cumulative Perpetual Preferred Stock
Document Information [Line Items]
Title of 12(b) Security	Depositary Shares, Each Representing a 1/40th Interest in a Share of 4.875% Fixed Rate Series A Non-Cumulative Perpetual Preferred Stock
Trading Symbol	WAFDP
Security Exchange Name	NASDAQ

CONSOLIDATED STATEMENTS OF FINA

CONSOLIDATED STATEMENTS OF FINANCIAL CONDITION - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022
ASSETS
Cash and cash equivalents	$ 645,862	$ 683,965
Available-for-sale securities, at fair value	2,059,837	2,051,037
Held-to-maturity securities, at amortized cost	453,443	463,299
Loans receivable, net of allowance for loan losses of $176,797 and $172,808	16,993,588	16,113,564
Interest receivable	75,316	63,872
Premises and equipment, net	240,360	243,062
Real estate owned	6,117	6,667
FHLB and FRB stock	133,073	95,073
Bank owned life insurance	238,370	237,931
Intangible assets, including goodwill of $303,457 and $303,457	308,767	309,009
Other assets	499,078	504,652
Total assets	21,653,811	20,772,131
Customer accounts
Transaction deposit accounts	12,547,832	12,691,527
Time deposit accounts	3,412,203	3,338,043
Total customer accounts	15,960,035	16,029,570
FHLB advances	3,075,000	2,125,000
Advance payments by borrowers for taxes and insurance	17,626	50,051
Federal and state income tax liabilities, net	16,995	3,306
Accrued expenses and other liabilities	259,774	289,944
Total liabilities	19,329,430	18,497,871
Commitments and contingencies (see Note I)
Shareholders’ equity
Preferred stock, $1.00 par value, 5,000,000 shares authorized; 300,000 and 300,000 shares issued; 300,000 and 300,000 shares outstanding	300,000	300,000
Common stock, $1.00 par value, 300,000,000 shares authorized; 136,373,350 and 136,270,886 shares issued; 65,387,745 and 65,330,126 shares outstanding	136,373	136,271
Additional paid-in capital	1,689,209	1,686,975
Accumulated other comprehensive income (loss), net of taxes	41,726	52,481
Treasury stock, at cost; 70,985,605 and 70,940,760 shares	(1,591,935)	(1,590,207)
Retained earnings	1,749,008	1,688,740
Total stockholders' equity	2,324,381	2,274,260
Total liabilities and shareholders' equity	$ 21,653,811	$ 20,772,131

CONSOLIDATED STATEMENTS OF FI_2

CONSOLIDATED STATEMENTS OF FINANCIAL CONDITION (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022
Statement of Financial Position [Abstract]
Allowance for credit losses on loans	$ 176,797	$ 172,808
Goodwill	$ 303,457	$ 303,457
Preferred stock, par value (in dollars per share)	$ 1	$ 1
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	300,000	300,000
Preferred stock, shares outstanding (in shares)	300,000	300,000
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	300,000,000	300,000,000
Common stock, shares issued (in shares)	136,373,350	136,270,886
Common stock, shares outstanding (in shares)	65,387,745	65,330,126
Treasury stock, shares (in shares)	70,985,605	70,940,760

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
INTEREST INCOME
Loans receivable	$ 203,946	$ 138,509
Mortgage-backed securities	10,613	4,792
Investment securities and cash equivalents	18,860	7,139
Total Income	233,419	150,440
INTEREST EXPENSE
Customer accounts	31,646	8,461
FHLB advances	18,974	7,843
Total interest expense	50,620	16,304
Net interest income	182,799	134,136
Provision for credit losses	2,500	500
Net interest income after provision (release)	180,299	133,636
OTHER INCOME
Gain (loss) on sale of investment securities	0	81
Loan fee income	$ 1,502	$ 1,921
Revenue, Product and Service [Extensible Enumeration]	Deposit Account [Member]	Deposit Account [Member]
Deposit fee income	$ 6,353	$ 6,443
Other income	6,169	10,236
Total other income	14,024	18,681
OTHER EXPENSE
Compensation and benefits	49,070	47,425
Occupancy	10,102	10,090
FDIC insurance premiums	3,675	3,100
Product delivery	4,621	4,721
Information technology	12,329	11,421
Other expense	12,481	12,856
Total other expense	92,278	89,613
Gain (loss) on real estate owned, net	(112)	562
Income before income taxes	101,933	63,266
Income tax expense	22,424	12,985
Net income	79,509	50,281
Dividends on preferred stock	3,656	3,656
Net income available to common shareholders	$ 75,853	$ 46,625
PER SHARE DATA
Basic earnings per common share (in dollars per share)	$ 1.16	$ 0.72
Diluted earnings per common share (in dollars per share)	1.16	0.71
Dividends paid on common stock (in dollars per share)	$ 0.24	$ 0.23
Basic weighted average number of shares outstanding (in shares)	65,341,974	65,207,837
Diluted weighted average number of shares outstanding (in shares)	65,430,690	65,350,174

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Statement of Comprehensive Income [Abstract]
Net income	$ 79,509	$ 50,281
Other comprehensive income (loss) net of tax:
Net unrealized gain (loss) during the period on available-for-sale investment securities, net of tax of $1,659 and $3,864	(5,521)	(12,934)
Reclassification adjustment of net (gain) loss from sale of available-for-sale securities included in net income, net of tax of $0 and $(19)	0	62
Net unrealized gain (loss) from investment securities, net of reclassification adjustment	(5,521)	(12,872)
Net unrealized gain (loss) during the period on borrowings cash flow hedges, net of tax of $1,572 and $(1,483)	(5,234)	4,963
Net unrealized gain (loss) in cash flow hedging instruments, net of reclassification adjustment	(5,234)	4,963
Other comprehensive income (loss)	(10,755)	(7,909)
Comprehensive income	$ 68,754	$ 42,372

CONSOLIDATED STATEMENTS OF CO_2

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Statement of Comprehensive Income [Abstract]
Related tax benefit (expense) for net unrealized gain (loss) on available-for-sale debt securities	$ 1,659	$ 3,864
Related tax benefit (expense) for reclassification adjustment of net (gain) loss included in net income during the period from sale of available-for-sale securities	0	(19)
Related tax benefit (expense) for net unrealized gain (loss) on borrowing cash flow hedges	$ 1,572	$ (1,483)

CONSOLIDATED STATEMENTS OF SHAR

CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Preferred Stock	Common Stock	Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Treasury Stock
Balance, beginning of period at Sep. 30, 2021	$ 2,126,064	$ 300,000	$ 135,993	$ 1,678,622	$ 1,528,611	$ 69,785	$ (1,586,947)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	50,281				50,281
Other comprehensive income (loss)	(7,909)					(7,909)
Dividends on common stock	(14,899)				(14,899)
Dividends on preferred stock	(3,656)				(3,656)
Proceeds from stock-based awards	828		30	798
Stock-based compensation expense	1,390		173	1,217
Treasury stock acquired	(2,973)						(2,973)
Balance, end of period at Dec. 31, 2021	2,149,126	300,000	136,196	1,680,637	1,560,337	61,876	(1,589,920)
Balance, beginning of period at Sep. 30, 2022	2,274,260	300,000	136,271	1,686,975	1,688,740	52,481	(1,590,207)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	79,509				79,509
Other comprehensive income (loss)	(10,755)					(10,755)
Dividends on common stock	(15,585)				(15,585)
Dividends on preferred stock	(3,656)				(3,656)
Proceeds from stock-based awards	765		25	740
Stock-based compensation expense	1,571		77	1,494
Treasury stock acquired	(1,728)						(1,728)
Balance, end of period at Dec. 31, 2022	$ 2,324,381	$ 300,000	$ 136,373	$ 1,689,209	$ 1,749,008	$ 41,726	$ (1,591,935)

CONSOLIDATED STATEMENTS OF SH_2

CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares	3 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Statement of Stockholders' Equity [Abstract]
Dividends paid on common stock (in dollars per share)	$ 0.24	$ 0.23
Dividends paid on preferred stock (in dollars per share)	$ 12.1875	$ 12.1875

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 79,509	$ 50,281
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization, accretion and other, net	1,613	7,944
Stock-based compensation expense	1,571	1,390
Provision for credit losses	2,500	500
Loss (gain) on sale of investment securities	0	(81)
Gain on bank owned life insurance	(821)	0
Net realized (gain) loss on sales of premises, equipment, and real estate owned	(230)	(355)
Decrease (increase) in accrued interest receivable	(11,444)	(1,115)
Decrease (increase) in federal and state income tax receivable	0	3,877
Decrease (increase) in cash surrender value of bank owned life insurance	(439)	(1,397)
Decrease (increase) in other assets	3,134	(3,422)
Increase (decrease) in federal and state income tax liabilities	16,920	5,090
Increase (decrease) in accrued expenses and other liabilities	(26,213)	(35,871)
Net cash provided by (used in) operating activities	66,100	26,841
CASH FLOWS FROM INVESTING ACTIVITIES
Origination of loans and principal repayments, net	(802,470)	(347,596)
Loans purchased	(77,484)	(413,326)
FHLB & FRB stock purchased	(176,000)	(56,000)
FHLB & FRB stock redeemed	138,000	56,000
Available-for-sale securities purchased	(115,909)	0
Principal payments and maturities of available-for-sale securities	100,340	170,847
Proceeds from sales of available-for-sale securities	0	4,510
Principal payments and maturities of held-to-maturity securities	9,793	38,679
Proceeds from sales of real estate owned	744	2,883
Equity securities purchased	(7,500)	0
Proceeds from sales of premises and equipment	664	2
Premises and equipment purchased and REO improvements	(2,217)	(2,771)
Net cash provided by (used in) investing activities	(932,039)	(546,772)
CASH FLOWS FROM FINANCING ACTIVITIES
Net increase (decrease) in customer accounts	(69,535)	359,934
Proceeds from borrowings	4,400,000	1,400,000
Repayments of borrowings	(3,450,000)	(1,400,000)
Proceeds from stock-based awards	765	828
Dividends paid on common stock	(15,585)	(14,899)
Dividends paid on preferred stock	(3,656)	(3,656)
Treasury stock purchased	(1,728)	(2,973)
Increase (decrease) in advances payments by borrowers for taxes and insurance	(32,425)	(29,465)
Net cash provided by (used in) financing activities	827,836	309,769
Increase (decrease) in cash and cash equivalents	(38,103)	(210,162)
Cash, cash equivalents and restricted cash at beginning of period	683,965	2,090,809
Cash, cash equivalents and restricted cash at end of period	645,862	1,880,647
Non-cash investing activities
Real estate acquired through foreclosure	95	0
Other personal property acquired through foreclosure	0	422
Non-cash financing activities
Preferred stock dividend payable	3,656	3,656
Cash paid (received) during the period for
Interest	48,195	13,275
Income taxes	$ 1,016	$ 0

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Dec. 31, 2022
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Company and Nature of Operations - Washington Federal Bank, a federally-insured Washington state chartered commercial bank dba WaFd Bank (the “Bank” or “WaFd Bank”), was founded on April 24, 1917 in Ballard, Washington and is engaged primarily in providing lending, depository, insurance and other banking services to consumers, mid-sized to large businesses, and owners and developers of commercial real estate. Washington Federal, Inc., a Washington corporation, was formed as the Bank’s holding company in November, 1994. As used throughout this document, the terms “Washington Federal” or the “Company” or “we” or “us” and “our” refer to Washington Federal, Inc. and its consolidated subsidiaries, and the term “Bank” refers to the operating subsidiary, Washington Federal Bank. The Company is headquartered in Seattle, Washington. The Bank conducts its activities through a network of 200 bank branches located in Washington, Oregon, Idaho, Utah, Arizona, Nevada, New Mexico and Texas. Basis of Presentation - The Company has prepared the consolidated unaudited interim financial statements included in this report. All intercompany transactions and accounts have been eliminated in consolidation. The preparation of financial statements, in conformity with accounting principles generally accepted in the United States of America (“GAAP”), requires management to make estimates and assumptions that affect amounts reported in the financial statements. Actual results could differ from these estimates. In the opinion of management, all adjustments (consisting only of normal recurring adjustments) necessary for a fair presentation are reflected in the interim financial statements. The information included in this Form 10-Q should be read in conjunction with the financial statements and related notes in the Company's 2022 Annual Report on Form 10-K filed with the Securities and Exchange Commission ("SEC") on November 18, 2022 ("2022 Annual Financial Statements"). Interim results are not necessarily indicative of results for a full year. Summary of Significant Accounting Policies - The significant accounting policies used in preparation of the Company's consolidated financial statements are disclosed in its 2022 Annual Financial Statements. There have not been any significant changes in the Company's significant accounting policies compared to those contained in its 2022 Annual Financial Statements for the year ended September 30, 2022. Preferred Stock - On February 8, 2021, in connection with an underwritten public offering, the Company issued 300,000 shares of 4.875% Noncumulative Perpetual Series A Preferred Stock (“Series A Preferred Stock”). Net proceeds, after underwriting discounts and expenses, were $293,325,000. The public offering consisted of the issuance and sale of 12,000,000 depositary shares, each representing a 1/40 th interest in a share of the Series A Preferred Stock, at a public offering price of $25.00 per depositary share. Holders of the depositary shares are entitled to all proportional rights and preferences of the Series A Preferred Stock (including dividend, voting, redemption and liquidation rights). The depositary shares are traded on the NASDAQ Global Select Market under the symbol "WAFDP." The Series A Preferred Stock is redeemable at the option of the Company, subject to all applicable regulatory approvals, on or after April 15, 2026. Restricted Cash Balances - Based on the level of vault cash on hand, the Company was not required to maintain cash reserve balances with the Federal Reserve Bank as of December 31, 2022. As of December 31, 2022 and September 30, 2022, the Company held counterparty cash collateral of $280,400,000 and pledged cash collateral to counterparties of $284,400,000, respectively, related to derivative contracts. Equity Securities - The Company records equity securities within Other assets in its Consolidated Statements of Financial Condition. These equity investments are accounted for under different methods. • Low-income housing tax credit investments are accounted for under the proportional amortization method in accordance with Accounting Standards Update (“ASU”) 2014-01, Equity Method and Joint Ventures (Topic 323) . • For other equity investments where the Company has significant influence, the Company applies the equity method of accounting, which adjusts the carrying value of the investment to recognize a proportionate share of the financial results of the investment entity, regardless of whether any distribution is made. Any adjustments to the fair value of these investments are recorded in Other income in the Consolidated Statements of Operations. • For other equity investments where neither ASU 2014-01 nor the equity method of accounting is applicable, the Company applies the fair value adjustment method of ASU 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities (Subtopic 825-10) . Any adjustments to the fair value of these investments are recorded in Other income in the Consolidated Statements of Operations. Fair value is determined by reference to readily determinable market values if applicable. Equity investments that do not have readily determinable fair values (non-marketable) are generally accounted for at cost minus impairment, if any, plus or minus changes resulting from observable transactions involving the same or similar investments from the same issuer, also referred to as the measurement alternative. Under the NAV expedient for fair value measurement, equity investments in qualified real estate funds can use the net asset value (“NAV”) determined by the fund as fair value for the investment. At December 31, 2022, equity investments held by the Company and recorded at NAV had a carrying amount of $38,385,000 and a remaining unfunded commitment of $7,511,000. These NAV based investments cannot be transferred without consent and we do not have redemption rights. Equity investments measured at NAV are not classified in the fair value hierarchy. Allowance for Credit Losses (Loans Receivable) - The Company maintains an allowance for credit losses (“ACL”) for the expected credit losses of the loan portfolio as well as unfunded loan commitments. The amount of ACL is based on ongoing, quarterly assessments by management. The current expected credit loss methodology (“CECL”) requires an estimate of the credit losses expected over the life of an exposure (or pool of exposures) and replaces the incurred loss methodology’s threshold that delayed the recognition of a credit loss until it was probable a loss event was incurred. The ACL consists of the allowance for loan losses and the reserve for unfunded commitments. The estimate of expected credit losses under the CECL methodology is based on relevant information about past events, current conditions, and reasonable and supportable forecasts that affect the collectability of the reported amounts. Historical loss experience is generally the starting point for estimating expected credit losses. We then consider whether the historical loss experience should be adjusted for asset-specific risk characteristics or current conditions at the reporting date that did not exist over the period that historical experience was based for each loan type. Finally, we consider forecasts about future economic conditions or changes in collateral values that are reasonable and supportable. Portfolio segment is defined as the level at which an entity develops and documents a systematic methodology to determine its ACL. The Company has designated two loan portfolio segments, commercial loans and consumer loans. These loan portfolio segments are further disaggregated into classes, which represent loans of similar type, risk characteristics, and methods for monitoring and assessing credit risk. The commercial loan portfolio segment is disaggregated into five classes: multi-family, commercial real estate, commercial and industrial, construction, and land acquisition and development. The risk of loss for the commercial loan portfolio segment is generally most indicated by the credit risk rating assigned to each borrower. Commercial loan risk ratings are determined by experienced senior credit officers based on specific facts and circumstances and are subject to periodic review by an independent internal team of credit specialists. The consumer loan portfolio segment is disaggregated into five classes: single-family-residential mortgage, custom construction, consumer lot loans, home equity lines of credit, and other consumer. The risk of loss for the consumer loan portfolio segment is generally most indicated by delinquency status and general economic factors. Each commercial and consumer loan portfolio class may also be further segmented based on risk characteristics. For most of our loan portfolio classes, the historical loss experience is determined using a cohort methodology. This method pools loans into groups (“cohorts”) sharing similar risk characteristics and tracks each cohort’s net charge-offs over the lives of the loans to calculate a historical loss rate. The historical loss rates for each cohort are then averaged to calculate an overall historical loss rate which is applied to the current loan balance to arrive at the quantitative baseline portion of the allowance for credit losses for the respective loan portfolio class. For certain loan portfolio classes, the Company determined there was not sufficient historical loss information to calculate a meaningful historical loss rate using the cohort methodology. For any such loan portfolio class, the weighted-average remaining maturity (“WARM”) methodology is being utilized until sufficient historical loss data is obtained. The WARM method multiplies an average annual loss rate by the expected remaining life of the loan pool to arrive at the quantitative baseline portion of the allowance for credit losses for the respective loan portfolio class. The Company also considers qualitative adjustments to the historical loss rate for each loan portfolio class. The qualitative adjustments for each loan class consider the conditions over the period from which historical loss experience was based and are split into two components: 1) asset or class specific risk characteristics or current conditions at the reporting date related to portfolio credit quality, remaining payments, volume and nature, credit culture and management, business environment or other management factors and 2) reasonable and supportable forecast of future economic conditions and collateral values. The Company performs a quarterly asset quality review which includes a review of forecasted gross charge-offs and recoveries, nonperforming assets, criticized loans, risk rating migration, delinquencies, etc. The asset quality review is performed by management and the results are used to consider a qualitative overlay to the quantitative baseline. The second qualitative adjustment noted above, economic conditions and collateral values, encompasses a one-year reasonable and supportable forecast period. The overlay adjustment for the reasonable and supportable forecast assumes an immediate reversion after the one-year forecast period to historical loss rates for the remaining life of the respective loan pool. When management deems it to be appropriate, the Company establishes a specific reserve for individually evaluated loans that do not share similar risk characteristics with the loans included in each respective loan pool. These individually evaluated loans are removed from their respective pools and typically represent collateral dependent loans but may also include other non-performing loans or troubled debt restructurings (“TDRs”). In addition, the Company individually evaluates “reasonably expected” TDRs, which are identified by the Company as a loan expected to be classified as a TDR within the next six months. Management judgment is utilized to make this determination. Allowance for Credit Losses (Held-to-Maturity Debt Securities) - For held-to-maturity (“HTM”) debt securities, the Company is required to utilize a CECL methodology to estimate expected credit losses. Substantially all of the Company’s HTM debt securities are issued by U.S. government agencies or U.S. government-sponsored enterprises. These securities carry the explicit and/or implicit guarantee of the U.S. government and have a long history of zero credit loss. See Note F "Fair Value Measurements" for more information about HTM debt securities. Allowance for Credit Losses (Available-for-Sale Debt Securities) - The impairment model for available-for-sale (“AFS”) debt securities differs from the CECL methodology applied for HTM debt securities because AFS debt securities are measured at fair value rather than amortized cost. For AFS debt securities in an unrealized loss position, the Company first assesses whether it intends to sell, or it is more likely than not that it will be required to sell, the security before recovery of its amortized cost basis. If either criteria is met, the security’s amortized cost basis is written down to fair value through income. For AFS debt securities where neither of the criteria are met, the Company evaluates whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, management considers the extent to which fair value is less than amortized cost, any changes to the credit rating of the security by a rating agency, and adverse conditions specifically related to the security, among other factors. If this assessment indicates that a credit loss exists, the present value of cash flows expected to be collected from the security are compared to the amortized cost basis of the security. If the present value of cash flows expected to be collected is less than the amortized cost basis, a credit loss exists and an allowance for credit losses is recorded for the credit loss, limited to the amount that the fair value is less than the amortized cost basis. Any remaining discount that has not been recorded through an allowance for credit losses is recognized in other comprehensive income. Changes in the allowance for credit losses are recorded as a provision (or recapture of) for credit losses. Losses are charged against the allowance when management believes the uncollectibility of an AFS security is confirmed or when either of the criteria regarding intent or requirement to sell is met. See Note F "Fair Value Measurements" for more information about AFS debt securities. Accrued Interest Receivable - The Company made the following elections regarding accrued interest receivable (“AIR”): • Presenting accrued interest receivable balances separately from their underlying instruments within the consolidated statements of financial condition. • Excluding accrued interest receivable that is included in the amortized cost of financing receivables from related disclosure requirements. • Continuing our policy to write off accrued interest receivable by reversing interest income in cases where the Company does not reasonably expect to receive payment. • Not measuring an allowance for credit losses for accrued interest receivable due to the Company’s policy of writing off uncollectible accrued interest receivable balances in a timely manner, as described above. Non-Accrual Loans - Loans are placed on non-accrual status when, in the judgment of management, the probability of collection of interest is deemed to be insufficient to warrant further accrual. When a loan is placed on non-accrual status, previously accrued but unpaid interest is deducted from interest income. The Bank does not accrue interest on loans 90 days or more past due. If payment is made on a loan so that the loan becomes less than 90 days past due, and the Bank expects full collection of principal and interest, the loan is returned to full accrual status. Any interest ultimately collected is credited to income in the period of recovery. A loan is charged-off when the loss is estimable and it is confirmed that the borrower is not expected to be able to meet contractual obligations. If a consumer loan is on non-accrual status before becoming a TDR it will stay on non-accrual status following restructuring until it has been performing for at least six months, at which point it may be moved to accrual status. If a loan is on accrual status before it becomes a TDR, and management concludes that full repayment is probable based on internal evaluation, it will remain on accrual status following restructuring. If the restructured consumer loan does not perform, it is placed on non-accrual status when it is 90 days delinquent. For commercial loans, six consecutive payments on newly restructured loan terms are required prior to returning the loan to accrual status. In some instances, after the required six consecutive payments are made, management will conclude that collection of the entire principal and interest due is still in doubt. In those instances, the loan will remain on non-accrual status. Collateral-Dependent Loans - A financial asset is considered collateral-dependent when the debtor is experiencing financial difficulty and repayment is expected to be provided substantially through the sale or operation of the collateral. For all classes of loans and leases deemed collateral-dependent, the Company elected the practical expedient to estimate expected credit losses based on the collateral’s fair value less cost to sell. In most cases, the Company records a partial charge-off to reduce the loan’s carrying value to the collateral’s fair value less cost to sell. Substantially all of the collateral consists of various types of real estate including residential properties; commercial properties such as retail centers, office buildings, and lodging; agriculture land; and vacant land. Off-balance-sheet credit exposures - The only material off-balance-sheet credit exposures are unfunded loan commitments, which had a combined balance of $4,822,769,000 and $4,947,570,000 at December 31, 2022 and September 30, 2022, respectively. The reserve for unfunded commitments is recognized as a liability (other liabilities in the consolidated statements of financial condition), with adjustments to the reserve recognized through provision for credit losses in the consolidated statements of income. The reserve for unfunded commitments represents the expected lifetime credit losses on off-balance sheet obligations such as commitments to extend credit and standby letters of credit. However, a liability is not recognized for commitments that are unconditionally cancellable by the Company. The reserve for unfunded commitments is determined by estimating future draws, including the effects of risk mitigation actions, and applying the expected loss rates on those draws. Loss rates are estimated by utilizing the same loss rates calculated for the allowance for credit losses related to the respective loan portfolio class. See Note I “Commitments and Contingencies” for more information.

New Accounting Pronouncements

New Accounting Pronouncements	3 Months Ended
	Dec. 31, 2022
Accounting Changes and Error Corrections [Abstract]
New Accounting Pronouncements	New Accounting Pronouncements In March 2020, the Financial Accounting Standards Board (“FASB”) issued ASU 2020-04, Reference Rate Reform (Topic 848). The amendments in this ASU provide temporary, optional guidance to ease the potential burden in accounting for reference rate reform. The ASU provides optional expedients and exceptions for applying GAAP to transactions affected by reference rate reform if certain criteria are met. The ASU primarily includes relief related to contract modifications and hedging relationships, as well as providing a one-time election for the sale or transfer of debt securities classified as held-to-maturity. This guidance is effective immediately and the amendments were originally to be applied prospectively through December 31, 2022. However, the FASB issued ASU 2022-06, deferring the sunset date to December 31, 2024. The Company has evaluated the regulatory requirements to cease the use of LIBOR and has put in place systems and capabilities for this purpose. The adoption of this ASU is not expected to have a material impact on the Company's consolidated financial statements. In March 2022, the FASB issued ASU 2022-01, Derivatives and Hedging (Topic 815) . The amendments in this ASU clarify the guidance on ASC 815 on fair value hedge accounting of interest rate risk for portfolios and financial assets. Among other things, the amended guidance establishes the "last-of-layer" method for making the fair value hedge accounting for these portfolios more accessible and renames that method the "portfolio layer" method. The amendments in this ASU are effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. We do not expect the amendments to have a material effect on our consolidated financial statements. In March 2022, the FASB issued ASU 2022-02, Financial Instruments - Credit Losses (Topic 326) . The amendments in this ASU eliminate the guidance on troubled debt restructurings while enhancing disclosure requirements for certain loan refinancing and restructurings by creditors made to borrowers experiencing financial difficulties. The ASU also requires that entities disclose current-period gross charge-offs by year of origination for loans and leases. The amendments in this ASU are effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. We do not expect the amendments to have a material effect on our consolidated financial statements.

Dividends and Share Repurchases

Dividends and Share Repurchases	3 Months Ended
	Dec. 31, 2022
Stockholders' Equity Note [Abstract]
Dividends and Share Repurchases	Dividends and Share Repurchases On December 2, 2022, the Company paid a regular dividend on common stock of $0.24 per share, which represented the 159 th consecutive quarterly cash dividend. Dividends per share were $0.24 and $0.23 for the quarters ended December 31, 2022 and 2021, respectively. For the three months ended December 31, 2022, the Company repurchased 44,845 shares at an average price of $38.53. As of December 31, 2022, there are 3,679,499 remaining shares authorized to be repurchased under the current Board approved share repurchase program.

Loans Receivable

Loans Receivable	3 Months Ended
	Dec. 31, 2022
Receivables [Abstract]
Loans Receivable	Loans Receivable For a detailed discussion of loans and credit quality, including accounting policies and the CECL methodology used to estimate the allowance for credit losses, see Note A "Summary of Significant Accounting Policies" above. The Company's loans held for investment are divided into two portfolio segments, commercial loans and consumer loans, with each of those segments further split into loan classes for purposes of estimating the allowance for credit losses. The following table is a summary of loans receivable by loan portfolio segment and class. December 31, 2022 September 30, 2022 (In thousands) (In thousands) Commercial loans Multi-family $ 2,713,331 13.4 % $ 2,645,801 13.7 % Commercial real estate 3,237,073 16.0 3,133,660 16.2 Commercial & industrial 2,628,131 13.0 2,350,984 12.1 Construction 4,055,474 20.0 3,784,388 19.5 Land - acquisition & development 253,682 1.2 291,301 1.5 Total commercial loans 12,887,691 63.6 12,206,134 63.0 Consumer loans Single-family residential 6,013,410 29.7 5,771,862 29.8 Construction - custom 926,126 4.6 974,652 5.0 Land - consumer lot loans 148,246 0.7 153,240 0.8 HELOC 212,123 1.0 203,528 1.0 Consumer 73,115 0.4 75,543 0.4 Total consumer loans 7,373,020 36.4 7,178,825 37.0 Total gross loans 20,260,711 100 % 19,384,959 100 % Less: Allowance for credit losses on loans 176,797 172,808 Loans in process 2,997,839 3,006,023 Net deferred fees, costs and discounts 92,487 92,564 Total loan contra accounts 3,267,123 3,271,395 Net loans $ 16,993,588 $ 16,113,564 The Company elected to exclude accrued interest receivable from the amortized cost basis of loans for disclosure purposes and from the calculations of estimated credit losses. As of December 31, 2022, and September 30, 2022, AIR for loans totaled $67,169,000 and $57,070,000, respectively, and is included in the Interest receivable line item balance on the Company’s consolidated statements of financial condition. Loans in the amount of $8,636,895,000 and $8,224,951,000 at December 31, 2022 and September 30, 2022, respectively, were pledged to secure borrowings from the Federal Home Loan Bank ("FHLB") as part of our liquidity management strategy. The FHLB does not have the right to sell or re-pledge these loans. The following table sets forth the amortized cost basis of non-accrual loans and loans 90 days or more past due and accruing. December 31, 2022 September 30, 2022 (In thousands, except ratio data) Non-accrual Non-accrual with no ACL 90 days or more past due and accruing Non-accrual Non-accrual with no ACL 90 days or more past due and accruing Commercial loans Multi-family $ 5,879 $ — $ — $ 5,912 $ — $ — Commercial real estate 4,635 — — 4,691 — — Commercial & industrial 906 906 — 5,693 1,308 — Construction — — — — — — Land - acquisition & development — — — — — — Total commercial loans 11,420 906 — 16,296 1,308 — Consumer loans Single-family residential 17,084 — — 17,450 — — Construction - custom 435 — — 435 — — Land - consumer lot loans 71 — — 84 — — HELOC 134 — — 233 — — Consumer 36 — — 36 — — Total consumer loans 17,760 — — 18,238 — — Total non-accrual loans $ 29,180 $ 906 $ — $ 34,534 $ 1,308 $ — % of total loans 0.17 % 0.21 % The Company recognized interest income on non-accrual loans of approximately $534,000 in the three months ended December 31, 2022. If these loans had been on accrual status and performed according to their original contract terms, the Company would have recognized interest income of approximately $358,000 for the three months ended December 31, 2022. Recognized interest income for the three months ended December 31, 2022 was higher than what otherwise would have been recognized in the period due to the collection of past due amounts. Interest cash flows collected on non-accrual loans vary from period to period as those loans are brought current or are paid off. The following tables provide details regarding loan delinquencies by loan portfolio and class. December 31, 2022 Days Delinquent Based on $ Amount of Loans % based Type of Loan Loans Receivable (Amortized Cost) Current 30 60 90 Total Delinquent (In thousands, except ratio data) Commercial Loans Multi-family $ 2,695,759 $ 2,695,759 $ — $ — $ — $ — — % Commercial real estate 3,213,308 3,212,259 533 452 64 1,049 0.03 Commercial & industrial 2,621,266 2,620,020 261 81 904 1,246 0.05 Construction 1,637,499 1,636,565 934 — 934 0.06 Land - acquisition & development 191,162 191,162 — — — — — Total commercial loans 10,358,994 10,355,765 1,728 533 968 3,229 0.03 Consumer Loans Single-family residential 5,967,678 5,946,382 5,661 2,038 13,597 21,296 0.36 Construction - custom 408,563 408,128 — — 435 435 0.11 Land - consumer lot loans 147,078 146,969 49 — 60 109 0.07 HELOC 214,904 212,655 2,121 — 128 2,249 1.05 Consumer 73,168 72,777 54 174 163 391 0.53 Total consumer loans 6,811,391 6,786,911 7,885 2,212 14,383 24,480 0.36 Total Loans $ 17,170,385 $ 17,142,676 $ 9,613 $ 2,745 $ 15,351 $ 27,709 0.16 % Delinquency % 99.84% 0.06% 0.01% 0.09% 0.16% September 30, 2022 Days Delinquent Based on $ Amount of Loans % based Type of Loan Loans Receivable (Amortized Cost) Current 30 60 90 Total Delinquent (In thousands, except ratio data) Commercial Loans Multi-family $ 2,626,479 $ 2,626,479 $ — $ — $ — $ — — % Commercial real estate 3,111,112 3,110,056 538 450 68 1,056 0.03 Commercial & industrial 2,343,403 2,336,791 — 919 5,693 6,612 0.28 Construction 1,423,891 1,423,891 — — — — Land - acquisition & development 223,616 223,616 — — — — — Total commercial loans 9,728,501 9,720,833 538 1,369 5,761 7,668 0.08 Consumer Loans Single-family residential 5,726,979 5,708,996 2,796 1,316 13,871 17,983 0.31 Construction - custom 397,343 396,908 — — 435 435 0.11 Land - consumer lot loans 151,945 151,746 — 139 60 199 0.13 HELOC 206,033 205,605 155 46 227 428 0.21 Consumer 75,571 75,357 162 17 35 214 0.28 Total consumer loans 6,557,871 6,538,612 3,113 1,518 14,628 19,259 0.29 Total Loans $ 16,286,372 $ 16,259,445 $ 3,651 $ 2,887 $ 20,389 $ 26,927 0.17 % Delinquency % 99.83% 0.02% 0.02% 0.13% 0.17% Most TDRs are accruing and performing loans where the borrower has proactively approached the Company about modification due to temporary financial difficulties. Each request for modification is individually evaluated for merit and likelihood of success. The concession granted in a loan modification is typically a payment reduction through a rate reduction of between 100 to 200 basis points for a specific term, usually six We evaluate the credit quality of our loans based on regulatory risk ratings and also consider other factors. Based on this evaluation, the loans are assigned a grade and classified as follows: • Pass – the credit does not meet one of the definitions below. • Special mention – A special mention credit is considered to be currently protected from loss but is potentially weak. No loss of principal or interest is foreseen; however, proper supervision and management attention is required to deter further deterioration in the credit. Assets in this category constitute some undue and unwarranted credit risk but not to the point of justifying a risk rating of substandard. The credit risk may be relatively minor yet constitutes an unwarranted risk in light of the circumstances surrounding a specific asset. • Substandard – A substandard credit is an unacceptable credit. Additionally, repayment in the normal course is in jeopardy due to the existence of one or more well defined weaknesses. In these situations, loss of principal is likely if the weakness is not corrected. A substandard asset is inadequately protected by the current sound worth and paying capacity of the borrower or of the collateral pledged, if any. Assets so classified will have a well-defined weakness or weaknesses that jeopardize the collection or liquidation of the debt. Loss potential, while existing in the aggregate amount of substandard assets, does not have to exist in individual assets risk rated substandard. • Doubtful – A credit classified doubtful has all the weaknesses inherent in one classified substandard with the added characteristic that the weakness makes collection or liquidation in full, on the basis of currently existing facts, conditions and values, highly questionable and improbable. The probability of loss is high, but because of certain important and reasonably specific pending factors that may work to the advantage and strengthening of the asset, its classification as an estimated loss is deferred until its more exact status may be determined. Pending factors include proposed merger, acquisition, or liquidation procedures, capital injection, perfecting liens on additional collateral, and refinancing plans. • Loss – Credits classified loss are considered uncollectible and of such little value that their continuance as a bankable asset is not warranted. This classification does not mean that the asset has absolutely no recovery or salvage value, but rather it is not practical or desirable to defer writing off this asset even though partial recovery may be affected in the future. Losses should be taken in the period in which they are identified as uncollectible. Partial charge-off versus full charge-off may be taken if the collateral offers some identifiable protection. The following tables present by primary credit quality indicator, loan class, and year of origination, the amortized cost basis of loans receivable as of December 31, 2022 and September 30, 2022. December 31, 2022 Term Loans Amortized Cost Basis by Origination Year YTD 2023 2022 2021 2020 2019 Prior to 2019 Revolving Loans Revolving to Term Loans Total Loans Commercial loans Multi-family Pass $ 94,649 $ 666,795 $ 763,102 $ 486,468 $ 167,495 $ 464,692 $ 36,361 $ — $ 2,679,562 Substandard — 3,931 — 4,180 — 8,086 — — 16,197 Total $ 94,649 $ 670,726 $ 763,102 $ 490,648 $ 167,495 $ 472,778 $ 36,361 $ — $ 2,695,759 Commercial real estate Pass $ 130,440 $ 806,478 $ 722,298 $ 467,416 $ 296,176 $ 705,610 $ 1,375 $ — $ 3,129,793 Special Mention — — — — 1,382 — — — 1,382 Substandard — 5,562 1,584 26,609 30,517 15,291 2,570 — 82,133 Total $ 130,440 $ 812,040 $ 723,882 $ 494,025 $ 328,075 $ 720,901 $ 3,945 $ — $ 3,213,308 Commercial & industrial Pass $ 124,523 $ 272,160 $ 345,166 $ 134,933 $ 34,585 $ 211,323 $ 1,350,779 $ 1,911 $ 2,475,380 Special Mention — — 2,601 — — — 2,850 — 5,451 Substandard — 7,961 12,829 5,292 4,671 25,427 84,255 — 140,435 Total $ 124,523 $ 280,121 $ 360,596 $ 140,225 $ 39,256 $ 236,750 $ 1,437,884 $ 1,911 $ 2,621,266 Construction Pass $ 17,955 $ 651,808 $ 694,514 $ 155,086 $ 33,585 $ 375 $ 75,930 $ — $ 1,629,253 Substandard — 5,987 2,259 — — — — — 8,246 Total $ 17,955 $ 657,795 $ 696,773 $ 155,086 $ 33,585 $ 375 $ 75,930 $ — $ 1,637,499 Land - acquisition & development Pass $ 4,682 $ 88,588 $ 48,857 $ 17,530 $ 2,981 $ 25,932 $ 2,592 $ — $ 191,162 Total $ 4,682 $ 88,588 $ 48,857 $ 17,530 $ 2,981 $ 25,932 $ 2,592 $ — $ 191,162 Total commercial loans Pass $ 372,249 $ 2,485,829 $ 2,573,937 $ 1,261,433 $ 534,822 $ 1,407,932 $ 1,467,037 $ 1,911 $ 10,105,150 Special Mention — — 2,601 — 1,382 — 2,850 — 6,833 Substandard — 23,441 16,672 36,081 35,188 48,804 86,825 — 247,011 Total $ 372,249 $ 2,509,270 $ 2,593,210 $ 1,297,514 $ 571,392 $ 1,456,736 $ 1,556,712 $ 1,911 $ 10,358,994 December 31, 2022 Term Loans Amortized Cost Basis by Origination Year YTD 2023 2022 2021 2020 2019 Prior to 2019 Revolving Loans Revolving to Term Loans Total Loans Consumer loans Single-family residential Current $ 219,679 $ 1,148,027 $ 1,717,690 $ 768,368 $ 313,719 $ 1,778,899 $ — $ — $ 5,946,382 30 days past due — — 1,637 — 63 3,961 — — 5,661 60 days past due — — — — — 2,038 — — 2,038 90+ days past due — — — — 1,084 12,513 — — 13,597 Total $ 219,679 $ 1,148,027 $ 1,719,327 $ 768,368 $ 314,866 $ 1,797,411 $ — $ — $ 5,967,678 Construction - custom Current $ — $ 320,079 $ 82,349 $ 4,864 $ 358 $ 478 $ — $ — $ 408,128 90+ days past due — — 435 — — — — — 435 Total $ — $ 320,079 $ 82,784 $ 4,864 $ 358 $ 478 $ — $ — $ 408,563 Land - consumer lot loans Current $ 4,355 $ 50,736 $ 55,658 $ 15,336 $ 5,189 $ 15,695 $ — $ — $ 146,969 30 days past due — — — — — 49 — — 49 90+ days past due — — — — — 60 — — 60 Total $ 4,355 $ 50,736 $ 55,658 $ 15,336 $ 5,189 $ 15,804 $ — $ — $ 147,078 HELOC Current $ — $ — $ — $ — $ — $ 4,846 $ 207,284 $ 525 $ 212,655 30 days past due — — — — — 260 1,861 — 2,121 90+ days past due — — — — — — 128 — 128 Total $ — $ — $ — $ — $ — $ 5,106 $ 209,273 $ 525 $ 214,904 Consumer Current $ 108 $ 2,145 $ 9,986 $ 8,023 $ 203 $ 28,303 $ 24,009 $ — $ 72,777 30 days past due — — — — — 37 17 — 54 60 days past due — — — — 1 173 — — 174 90+ days past due — 2 — — 32 129 — — 163 Total $ 108 $ 2,147 $ 9,986 $ 8,023 $ 236 $ 28,642 $ 24,026 $ — $ 73,168 Total consumer loans Current $ 224,142 $ 1,520,987 $ 1,865,683 $ 796,591 $ 319,469 $ 1,828,221 $ 231,293 $ 525 $ 6,786,911 30 days past due — — 1,637 — 63 4,307 1,878 — 7,885 60 days past due — — — — 1 2,211 — — 2,212 90+ days past due — 2 435 — 1,116 12,702 128 — 14,383 Total $ 224,142 $ 1,520,989 $ 1,867,755 $ 796,591 $ 320,649 $ 1,847,441 $ 233,299 $ 525 $ 6,811,391

Allowance for Losses on Loans

Allowance for Losses on Loans	3 Months Ended
	Dec. 31, 2022
Receivables [Abstract]
Allowance for Losses on Loans	Allowance for Losses on Loans For a detailed discussion of loans and credit quality, including accounting policies and the CECL methodology used to estimate the allowance for credit losses, see Note A "Summary of Significant Accounting Policies." The following tables summarize the activity in the allowance for loan losses by loan portfolio segment and class. Three Months Ended December 31, 2022 Beginning Allowance Charge-offs Recoveries Provision & Ending Allowance (In thousands) Commercial loans Multi-family $ 12,013 $ — $ — $ 311 $ 12,324 Commercial real estate 25,814 — 4 1,562 27,380 Commercial & industrial 57,210 (82) 32 6,713 63,873 Construction 26,161 — — (28) 26,133 Land - acquisition & development 12,278 — 16 (3,722) 8,572 Total commercial loans 133,476 (82) 52 4,836 138,282 Consumer loans Single-family residential 25,518 — 430 (473) 25,475 Construction - custom 3,410 — — 90 3,500 Land - consumer lot loans 5,047 — — (905) 4,142 HELOC 2,482 — 1 105 2,588 Consumer 2,875 (146) 234 (153) 2,810 Total consumer loans 39,332 (146) 665 (1,336) 38,515 Total ACL - loans $ 172,808 $ (228) $ 717 $ 3,500 $ 176,797 (1) Provision & transfer amounts within the table do not include provision recapture for unfunded commitments of $1,000,000. Three Months Ended December 31, 2021 Beginning Allowance Charge-offs Recoveries Provision & Transfers (1) Ending Allowance (In thousands) Commercial loans Multi-family $ 16,949 $ — $ — $ (956) $ 15,993 Commercial real estate 23,437 (529) 44 2,770 25,722 Commercial & industrial 45,957 (43) 62 1,255 47,231 Construction 25,585 — 2,000 (2,819) 24,766 Land - acquisition & development 13,447 (2) 20 660 14,125 Total commercial loans 125,375 (574) 2,126 910 127,837 Consumer loans Single-family residential 30,978 — 405 (1,277) 30,106 Construction - custom 4,907 — — (1,188) 3,719 Land - consumer lot loans 4,939 (27) 5 67 4,984 HELOC 2,390 — 1 (26) 2,365 Consumer 2,711 (76) 251 (486) 2,400 Total consumer loans 45,925 (103) 662 (2,910) 43,574 Total loans $ 171,300 $ (677) $ 2,788 $ (2,000) $ 171,411 (1) Provision & transfer amounts within the table do not include the provision for unfunded commitments of $2,500,000. The Company recorded a $2,500,000 provision for credit losses for the three months ended December 31, 2022, compared with a provision for credit losses of $500,000 for the three months ended December 31, 2021. The provision in the three months ended December 31, 2022 was primarily due to reserving for growth in loans receivable largely offset by improvements in management's assessment of the credit quality of certain loan portfolios. The provision for the three months ended December 31, 2021 was primarily due to reserving for growth in loans receivable and changes in composition of the loan portfolio. Recoveries, net of charge-offs, totaled $489,000 for the three months ended December 31, 2022, compared to $2,111,000 during the three months ended December 31, 2021. Non-performing assets were $38,650,000, or 0.18% of total assets, at December 31, 2022, compared to $44,554,000, or 0.21% of total assets, at September 30, 2022. Non-accrual loans were $29,180,000 at December 31, 2022, compared to $34,534,000 at September 30, 2022. Delinquencies, as a percent of total loans, were 0.16% at December 31, 2022, compared to 0.17% at September 30, 2022. The Company has an asset quality review function that analyzes its loan portfolio and reports the results of the review to its Board of Directors on a quarterly basis. The single-family residential, HELOC and consumer portfolios are evaluated based on their performance as a pool of loans, since no single loan is individually significant or judged by its risk rating, size or potential risk of loss. The construction, land, multi-family, commercial real estate and commercial and industrial loans are risk rated on a loan by loan basis to determine the relative risk inherent in specific borrowers or loans. Based on that risk rating, the loans are assigned a grade and classified as described in Note D "Loans Receivable." The following tables provide the amortized cost of loans receivable based on risk rating categories as previously defined. December 31, 2022 Internally Assigned Grade Pass Special mention Substandard Doubtful Loss Total (In thousands, except ratio data) Loan type Commercial loans Multi-family $ 2,679,562 $ — $ 16,197 $ — $ — $ 2,695,759 Commercial real estate 3,129,793 1,382 82,133 — — 3,213,308 Commercial & industrial 2,475,380 5,451 140,435 — — 2,621,266 Construction 1,629,253 — 8,246 — — 1,637,499 Land - acquisition & development 191,162 — — — — 191,162 Total commercial loans 10,105,150 6,833 247,011 — — 10,358,994 Consumer loans Single-family residential 5,947,295 — 20,383 — — 5,967,678 Construction - custom 408,127 — 436 — — 408,563 Land - consumer lot loans 147,007 — 71 — — 147,078 HELOC 214,771 — 133 — — 214,904 Consumer 73,161 — 7 — — 73,168 Total consumer loans 6,790,361 — 21,030 — — 6,811,391 Total $ 16,895,511 $ 6,833 $ 268,041 $ — $ — $ 17,170,385 Total grade as a % of total loans 98.40 % 0.04 % 1.56 % — % — % September 30, 2022 Internally Assigned Grade Pass Special mention Substandard Doubtful Loss Total Gross Loans (In thousands, except ratio data) Loan type Commercial loans Multi-family $ 2,612,669 $ — $ 13,810 $ — $ — $ 2,626,479 Commercial real estate 3,054,241 1,594 55,277 — — 3,111,112 Commercial & industrial 2,196,767 31,656 114,980 — — 2,343,403 Construction 1,421,634 — 2,257 — — 1,423,891 Land - acquisition & development 223,616 — — — — 223,616 Total commercial loans 9,508,927 33,250 186,324 — — 9,728,501 Consumer loans Single-family residential 5,706,199 — 20,780 — — 5,726,979 Construction - custom 396,908 — 435 — — 397,343 Land - consumer lot loans 151,723 — 222 — — 151,945 HELOC 205,800 — 233 — — 206,033 Consumer 75,570 — 1 — — 75,571 Total consumer loans 6,536,200 — 21,671 — — 6,557,871 Total loans $ 16,045,127 $ 33,250 $ 207,995 $ — $ — $ 16,286,372 Total grade as a % of total gross loans 98.52 % 0.20 % 1.28 % — % — % The following tables provide information on amortized cost of loans receivable based on borrower payment activity. December 31, 2022 Performing Loans Non-Performing Loans Amount % of Total Amount % of Total (In thousands, except ratio data) Commercial loans Multi-family $ 2,689,880 99.8 % $ 5,879 0.2 % Commercial real estate 3,208,673 99.9 4,635 0.1 Commercial & industrial 2,620,360 100.0 906 — Construction 1,637,499 100.0 — 0.0 Land - acquisition & development 191,162 100.0 — — Total commercial loans 10,347,574 99.9 11,420 0.1 Consumer loans Single-family residential 5,950,594 99.7 17,084 0.3 Construction - custom 408,128 99.9 435 0.1 Land - consumer lot loans 147,007 100.0 71 0.0 HELOC 214,770 99.9 134 0.1 Consumer 73,132 100.0 36 0.0 Total consumer loans 6,793,631 99.7 17,760 0.3 Total loans $ 17,141,205 99.8 % $ 29,180 0.2 % September 30, 2022 Performing Loans Non-Performing Loans Amount % of Total Amount % of Total (In thousands, except ratio data) Commercial loans Multi-family $ 2,620,567 99.8 % $ 5,912 0.2 % Commercial real estate 3,106,421 99.8 4,691 0.2 Commercial & industrial 2,337,710 99.8 5,693 0.2 Construction 1,423,891 100.0 — — Land - acquisition & development 223,616 100.0 — — Total commercial loans 9,712,205 99.8 16,296 0.2 Consumer loans Single-family residential 5,709,529 99.7 17,450 0.3 Construction - custom 396,908 99.9 435 0.1 Land - consumer lot loans 151,861 99.9 84 0.1 HELOC 205,800 99.9 233 0.1 Consumer 75,535 100.0 36 0.0 Total consumer loans 6,539,633 99.7 18,238 0.4 Total loans $ 16,251,838 99.8 % $ 34,534 0.2 %

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Dec. 31, 2022
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements FASB ASC 820, Fair Value Measurement ("ASC 820") defines fair value as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. ASC 820 also establishes a fair value hierarchy that requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The standard describes three levels of inputs that may be used to measure fair value: Level 1: Quoted prices (unadjusted) for identical assets or liabilities in active exchange markets that the entity has the ability to access as of the measurement date. Level 2: Significant other observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active and other inputs that are observable or can be corroborated by observable market data. Level 3: Significant unobservable inputs that reflect a company’s own assumptions about the assumptions that market participants would use in pricing an asset or liability. The Company has established and documented the process for determining the fair values of its assets and liabilities, where applicable. Fair value is based on quoted market prices, when available, for identical or similar assets or liabilities. In the absence of quoted market prices, fair value is determined using valuation models or third-party appraisals. The following is a description of the valuation methodologies used to measure and report the fair value of financial assets and liabilities on a recurring or nonrecurring basis. Measured on a Recurring Basis Available-for-Sale Securities and Derivative Contracts Securities available for sale are recorded at fair value on a recurring basis. The fair value of debt securities are priced using model pricing based on the securities' relationship to other benchmark quoted prices as provided by an independent third party, and under GAAP are considered a Level 2 input method. Securities that are traded on active exchanges are measured using the closing price in an active market and are considered a Level 1 input method. The Company offers interest rate swaps to its variable rate borrowers who want to manage their interest rate risk. At the same time, the Company enters into the opposite trade with a counter party to offset its interest rate risk. The Company has also entered into commercial loan hedges, mortgage pool hedges and borrowings hedges using interest rate swaps. The fair value of these interest rate swaps are estimated by a third-party pricing service using a discounted cash flow technique. These are considered a Level 2 input method. The following tables present the balance and level in the fair value hierarchy of assets and liabilities that are measured at fair value on a recurring basis. December 31, 2022 Level 1 Level 2 Level 3 Total (In thousands) Financial Assets Available-for-sale securities: U.S. government and agency securities $ — $ 99,889 $ — $ 99,889 Asset-backed securities — 696,572 — 696,572 Municipal bonds — 35,054 — 35,054 Corporate debt securities — 316,487 — 316,487 Mortgage-backed securities Agency pass-through certificates — 911,835 — 911,835 Total available-for-sale securities — 2,059,837 — 2,059,837 Client swap program hedges — 63,383 — 63,383 Commercial loan fair value hedges — 2,446 — 2,446 Mortgage loan fair value hedges — 33,986 — 33,986 Borrowings cash flow hedges — 173,139 — 173,139 Total financial assets $ — $ 2,332,791 $ — $ 2,332,791 Financial Liabilities Client swap program hedges $ — $ 63,383 $ — $ 63,383 Total financial liabilities $ — $ 63,383 $ — $ 63,383 September 30, 2022 Level 1 Level 2 Level 3 Total (In thousands) Financial Assets Available-for-sale securities: U.S. government and agency securities $ — $ 39,354 $ — $ 39,354 Asset-backed securities — 767,001 767,001 Municipal bonds — 34,962 — 34,962 Corporate debt securities — 313,757 — 313,757 Mortgage-backed securities Agency pass-through certificates — 895,963 — 895,963 Total available-for-sale securities — 2,051,037 — 2,051,037 Client swap program hedges — 67,260 — 67,260 Commercial loan fair value hedges — 2,517 — 2,517 Mortgage loan fair value hedges — 36,765 — 36,765 Borrowings cash flow hedges — 179,945 — 179,945 Total financial assets $ — $ 2,337,524 $ — $ 2,337,524 Financial Liabilities Client swap program hedges $ — $ 67,260 $ — $ 67,260 Total financial liabilities $ — $ 67,260 $ — $ 67,260 Measured on a Nonrecurring Basis Certain assets and liabilities are measured at fair value on a nonrecurring basis after initial recognition such as collateral dependent loans and real estate owned ("REO"). REO consists principally of properties acquired through foreclosure. From time to time, and on a nonrecurring basis, adjustments using fair value measurements are recorded to reflect increases or decreases based on the discounted cash flows, the current appraisal or estimated value of the collateral or REO property. When management determines that the fair value of the collateral or the REO requires additional adjustments, either as a result of an updated appraised value or when there is no observable market price, the Company classifies the collateral dependent loan or real estate owned as Level 3. Level 3 assets recorded at fair value on a nonrecurring basis at December 31, 2022 included loans for which an allowance was established or a partial charge-off was recorded based on the fair value of collateral, as well as real estate owned where the fair value of the property was less than the cost basis. The following tables present the aggregated balance of assets that were measured at fair value on a nonrecurring basis at December 31, 2022 and December 31, 2021, and the total gains (losses) resulting from those fair value adjustments during the respective periods. The estimated fair value measurements are shown gross of estimated selling costs. December 31, 2022 Three Months Ended December 31, 2022 Level 1 Level 2 Level 3 Total Total Gains (Losses) (In thousands) (In thousands) Loans (1) $ — $ — $ — $ — $ (123) Real estate owned (2) — — — — — Balance at end of period $ — $ — $ — $ — $ (123) (1) The gains (losses) represent re-measurements of collateral-dependent loans. (2) The gains (losses) represent aggregate write-downs and charge-offs on real estate owned. December 31, 2021 Three Months Ended December 31, 2021 Level 1 Level 2 Level 3 Total Total Gains (Losses) (In thousands) (In thousands) Loans (1) $ — $ — $ 202 $ 202 $ (89) Real estate owned (2) — — 1,390 1,390 (504) Balance at end of period $ — $ — $ 1,592 $ 1,592 $ (593) (1) The gains (losses) represent re-measurements of collateral-dependent loans. (2) The gains (losses) represent aggregate write-downs and charge-offs on real estate owned. At December 31, 2022, there was $93,000 in foreclosed residential real estate properties held as REO. The recorded investment of consumer mortgage loans secured by residential real estate properties for which formal foreclosure proceedings were in process was $2,807,000. Fair Values of Financial Instruments FASB ASC 825, Financial Instruments ("ASC 825") requires disclosure of fair value information about financial instruments, whether or not recognized on the statement of financial condition, for which it is practicable to estimate those values. Certain financial instruments and all non-financial instruments are excluded from the disclosure requirements. Accordingly, the aggregate fair value estimates presented do not reflect the underlying fair value of the Company. Although management is not aware of any factors that would materially affect the estimated fair value amounts presented below, such amounts have not been comprehensively revalued for purposes of these financial statements since the dates shown, and therefore, estimates of fair value subsequent to those dates may differ significantly from the amounts presented below. December 31, 2022 September 30, 2022 Level in Fair Value Hierarchy Carrying Estimated Carrying Estimated ($ in thousands) Financial assets Cash and cash equivalents 1 $ 645,862 $ 645,862 $ 683,965 $ 683,965 Available-for-sale securities U.S. government and agency securities 2 99,889 99,889 39,354 39,354 Asset-backed securities 2 696,572 696,572 767,001 767,001 Municipal bonds 2 35,054 35,054 34,962 34,962 Corporate debt securities 2 316,487 316,487 313,757 313,757 Mortgage-backed securities Agency pass-through certificates 2 911,835 911,835 895,963 895,963 Total available-for-sale securities 2,059,837 2,059,837 2,051,037 2,051,037 Held-to-maturity securities Mortgage-backed securities Agency pass-through certificates 2 453,443 402,055 463,299 406,860 Total held-to-maturity securities 453,443 402,055 463,299 406,860 Loans receivable 3 16,993,588 16,310,687 16,113,564 15,417,635 FHLB and FRB stock 2 133,073 133,073 95,073 95,073 Other assets - client swap program hedges 2 63,383 63,383 67,260 67,260 Other assets - commercial fair value loan hedges 2 2,446 2,446 2,517 2,517 Other assets - mortgage loan fair value hedges 2 33,986 33,986 36,765 36,765 Other assets - borrowings cash flow hedges 2 173,139 173,139 179,945 179,945 Financial liabilities Time deposits 2 3,412,203 3,329,708 3,338,043 3,249,169 FHLB advances 2 3,075,000 3,067,487 2,125,000 1,940,813 Other liabilities - client swap program hedges 2 63,383 63,383 67,260 67,260 The following methods and assumptions were used to estimate the fair value of financial instruments: Cash and cash equivalents – The carrying amount of these items is a reasonable estimate of their fair value. Available-for-sale securities and held-to-maturity securities – Securities at fair value are primarily priced using model pricing based on the securities' relationship to other benchmark quoted prices as provided by an independent third party, and are considered a Level 2 input method. Equity securities that are exchange traded are considered a Level 1 input method. Loans receivable – Fair values are estimated first by stratifying the portfolios of loans with similar financial characteristics. Loans are segregated by type such as multi-family real estate, residential mortgage, construction, commercial, consumer and land loans. Each loan category is further segmented into fixed- and adjustable-rate interest terms. For residential mortgages and multi-family loans, the bank determined that its best exit price was by securitization. MBS benchmark prices are used as a base price, with further loan level pricing adjustments made based on individual loan characteristics such as FICO score, LTV, Property Type and occupancy. For all other loan categories an estimate of fair value is then calculated based on discounted cash flows using a discount rate offered and observed in the market on similar products, plus an adjustment for liquidity to reflect the non-homogeneous nature of the loans, as well as an annual loss rate based on historical losses to arrive at an estimated exit price fair value. Fair value for impaired loans is also based on recent appraisals or estimated cash flows discounted using rates commensurate with risk associated with the estimated cash flows. Assumptions regarding credit risk, cash flows and discount rates are judgmentally determined using available market information and specific borrower information. FHLB and FRB stock – The fair value is based upon the par value of the stock that equates to its carrying value. Time deposits – The fair value of time deposits is estimated by discounting the estimated future cash flows using rates offered for deposits with similar remaining maturities. FHLB advances – The fair value of FHLB advances and other borrowings is estimated by discounting the estimated future cash flows using rates currently available to the Company for debt with similar remaining maturities. Interest rate swaps – The Company offers interest rate swaps to its variable rate borrowers who want to manage their interest rate risk. At the same time, the Company enters into the opposite trade with a counterparty to offset its interest rate risk. The Company also uses interest rate swaps for various fair value hedges and cash flow hedges. The fair value of these interest rate swaps is estimated by a third-party pricing service using a discounted cash flow technique. The following tables provide details about the amortized cost and fair value of available-for-sale and held-to-maturity securities. December 31, 2022 Amortized Gross Unrealized Fair Yield Gains Losses ($ in thousands) Available-for-sale securities U.S. government and agency securities due 1 to 5 years $ 36,531 $ — $ (925) $ 35,606 4.33 % Over 10 years 64,060 223 — 64,283 3.90 Asset-backed securities 1 to 5 years 21,033 — (1,524) 19,509 4.58 5 to 10 years 67,783 — (1,025) 66,758 5.01 Over 10 years 627,579 365 (17,639) 610,305 5.12 Corporate debt securities due Within 1 year 75,000 29 (212) 74,817 5.08 1 to 5 years 151,531 232 (3,435) 148,328 4.49 5 to 10 years 114,116 — (20,774) 93,342 3.87 Municipal bonds due 5 to 10 years 5,743 — (360) 5,383 3.00 Over 10 years 29,861 350 (540) 29,671 5.85 Mortgage-backed securities Agency pass-through certificates 985,480 11 (73,656) 911,835 2.98 2,178,717 1,210 (120,090) 2,059,837 3.99 Held-to-maturity securities Mortgage-backed securities Agency pass-through certificates 453,443 23 (51,411) 402,055 2.88 453,443 23 (51,411) 402,055 2.88 $ 2,632,160 $ 1,233 $ (171,501) $ 2,461,892 3.80 % September 30, 2022 Amortized Gross Unrealized Fair Yield Gains Losses ($ in thousands) Available-for-sale securities U.S. government and agency securities due 1 to 5 years $ 40,403 $ — $ (1,049) $ 39,354 3.03 % Asset-backed securities 1 to 5 years 22,527 — (1,141) 21,386 3.27 5 to 10 years 82,962 4 (547) 82,419 3.53 Over 10 years 668,482 783 (6,069) 663,196 3.86 Corporate debt securities due Within 1 year 75,000 4 (200) 74,804 3.74 1 to 5 years 151,411 — (2,748) 148,663 3.59 5 to 10 years 114,414 — (24,124) 90,290 3.87 Municipal bonds due 5 to 10 years 5,751 — (361) 5,390 3.00 Over 10 years 29,871 400 (699) 29,572 5.85 Mortgage-backed securities Agency pass-through certificates 971,916 117 (76,070) 895,963 2.81 2,162,737 1,308 (113,008) 2,051,037 3.36 Held-to-maturity securities Mortgage-backed securities Agency pass-through certificates 463,299 22 (56,461) 406,860 2.88 463,299 22 (56,461) 406,860 2.88 $ 2,626,036 $ 1,330 $ (169,469) $ 2,457,897 3.28 % For AFS investment securities, there were purchases of $115,909,000 during the three months ended December 31, 2022 and no purchases during the three months ended December 31, 2021. There were no sales of AFS investment securities during the three months ended December 31, 2022 and $4,510,000 of sales during the prior year same period. For HTM investment securities, there were no purchases during the three months ended December 31, 2022 and no purchases during the three months ended December 31, 2021. There were no sales of HTM investment securities during the three months ended December 31, 2022 or December 31, 2021. Substantially all of the agency mortgage-backed securities have contractual due dates that exceed 10 years. The Company elected to exclude AIR from the amortized cost basis of debt securities disclosed throughout this footnote. For AFS securities, AIR totaled $7,063,000 and $5,694,000 as of December 31, 2022 and September 30, 2022, respectively. For HTM debt securities, AIR totaled $1,084,000 and $1,108,000 as of December 31, 2022 and September 30, 2022, respectively. AIR for securities is included in the Interest receivable line item balance on the Company’s consolidated statements of financial condition. The following tables show the gross unrealized losses and fair value of securities as of December 31, 2022 and September 30, 2022, by length of time that individual securities in each category have been in a continuous loss position. There were 227 and 223 securities with an unrealized loss as of December 31, 2022 and September 30, 2022, respectively. The decline in fair value since purchase is attributable to changes in interest rates. Because the Company does not intend to sell these securities and does not consider it more likely than not that it will be required to sell these securities before the recovery of amortized cost basis, which may be upon maturity, the Company does not consider these investments to have any credit impairment. December 31, 2022 Less than 12 months 12 months or more Total Unrealized Fair Unrealized Fair Unrealized Fair (In thousands) Available-for-sale securities Corporate debt securities $ (24,421) $ 217,278 $ — $ — $ (24,421) $ 217,278 Municipal bonds (900) 14,704 — — (900) 14,704 U.S. government and agency securities $ (120) $ 28,002 $ (805) $ 7,604 $ (925) $ 35,606 Asset-backed securities (16,304) 593,310 (3,884) 72,112 (20,188) 665,422 Mortgage-backed securities (59,338) 833,728 (14,318) 77,584 (73,656) 911,312 (101,083) 1,687,022 (19,007) 157,300 (120,090) 1,844,322 Held-to-maturity securities Mortgage-backed securities (51,411) 400,422 — — (51,411) 400,422 $ (152,494) $ 2,087,444 $ (19,007) $ 157,300 $ (171,501) $ 2,244,744 September 30, 2022 Less than 12 months 12 months or more Total Unrealized Fair Unrealized Fair Unrealized Fair (In thousands) Available-for-sale securities Corporate debt securities $ (27,072) $ 288,753 $ — $ — $ (27,072) $ 288,753 Municipal bonds due (1,061) 14,561 — — (1,061) 14,561 U.S. government and agency securities (1,049) 39,354 — — (1,049) 39,354 Asset-backed securities $ (6,374) $ 601,248 $ (1,383) $ 50,070 $ (7,757) $ 651,318 Mortgage-backed securities (63,738) 833,683 (12,331) 53,533 (76,069) 887,216 (99,294) 1,777,599 (13,714) 103,603 (113,008) 1,881,202 Held-to-maturity securities Mortgage-backed securities (56,461) 405,166 — — (56,461) 405,166 $ (155,755) $ 2,182,765 $ (13,714) $ 103,603 $ (169,469) $ 2,286,368 Substantially all of the Company’s held-to-maturity debt securities are issued by U.S. government agencies or U.S. government-sponsored enterprises. These securities carry the explicit and/or implicit guarantee of the U.S. government and have a long history of zero credit loss. Therefore, the Company did not record an allowance for credit losses for these securities as of December 31, 2022 or September 30, 2022. The Company does not believe that the AFS debt securities that were in an unrealized loss position have any credit loss impairment as of December 31, 2022 or September 30, 2022. The Company does not intend to sell the investment securities that were in an unrealized loss position and it is more likely than not the Company will not be required to sell the investment securities before recovery of their amortized cost basis, which may be at maturity. AFS debt securities issued by U.S. government agencies or U.S. government-sponsored enterprises carry the explicit and/or implicit guarantee of the U.S. government and have a long history of zero credit loss. Corporate debt securities and municipal bonds are considered to have an issuer of high credit quality (rated AA or higher) and the decline in fair value is due to changes in interest rates and other market conditions. The issuer continues to make timely principal and interest payments on the bonds. The fair value is expected to recover as the bonds approach maturity.

Derivatives and Hedging Activit

Derivatives and Hedging Activities	3 Months Ended
	Dec. 31, 2022
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives and Hedging Activities	Derivatives and Hedging Activities The following tables present the fair value, notional amount and balance sheet classification of derivative assets and liabilities at December 31, 2022 and September 30, 2022. December 31, 2022 Derivative Assets Derivative Liabilities Interest rate contract purpose Balance Sheet Location Notional Fair Value Balance Sheet Location Notional Fair Value (In thousands) (In thousands) Client swap program hedges Other assets $ 583,782 $ 63,383 Other liabilities $ 583,782 $ 63,383 Commercial loan fair value hedges Other assets 39,661 2,447 Other liabilities — — Mortgage loan fair value hedges Other assets 470,000 33,986 Other liabilities — — Borrowings cash flow hedges Other assets 1,000,000 173,139 Other liabilities — — $ 2,093,443 $ 272,955 $ 583,782 $ 63,383 September 30, 2022 Derivative Assets Derivative Liabilities Interest rate contract purpose Balance Sheet Location Notional Fair Value Balance Sheet Location Notional Fair Value (In thousands) (In thousands) Client swap program hedges Other assets $ 588,676 $ 67,260 Other liabilities $ 588,676 $ 67,260 Commercial loan fair value hedges Other assets 42,209 2,517 Other liabilities — — Mortgage loan fair value hedges Other assets 470,000 36,765 Other liabilities — — Borrowings cash flow hedges Other assets 1,000,000 179,945 Other liabilities — — $ 2,100,885 $ 286,487 $ 588,676 $ 67,260 The Company enters into interest rate swaps to hedge interest rate risk. These arrangements include hedges of individual fixed rate commercial loans and also hedges of a specified portion of pools of prepayable fixed rate mortgage loans under the "last of layer" method. These relationships qualify as fair value hedges under FASB ASC 815, Derivatives and Hedging ("ASC 815"), which provides for offsetting of the recognition of gains and losses of the respective interest rate swap and the hedged items. Gains and losses on interest rate swaps designated in these hedge relationships, along with the offsetting gains and losses on the hedged items attributable to the hedged risk, are recognized in current earnings within the same income statement line item. Upon electing to apply ASC 815 fair value hedge accounting, the carrying value of the hedged item is adjusted to reflect the cumulative impact of changes in fair value attributable to the hedged risk. The hedge basis adjustment remains with the hedged item until the hedged item is de-recognized from the balance sheet. The following tables present the impact of fair value hedge accounting on the carrying value of the hedged items at December 31, 2022 and September 30, 2022. (In thousands) December 31, 2022 Balance sheet line item in which hedged item is recorded Carrying value of hedged items Cumulative gain (loss) fair value hedge adjustment included in carrying amount of hedged items Loans receivable (1) (2) $ 1,131,282 $ (35,958) $ 1,131,282 $ (35,958) (1) Includes the amortized cost basis of the closed mortgage loan portfolios used to designate the hedging relationships in which the hedged items are the last layer expected to be remaining at the end of the hedging relationships. At December 31, 2022, the amortized cost basis of the closed loan portfolios used in the hedging relationships was $1,094,211,000, the cumulative basis adjustment associated with the hedging relationships was $(33,423,000), and the amount of the designated hedged items was $470,000,000. (2) Includes the amortized cost basis of commercial loans designated in fair value hedging relationships. At December 31, 2022, the amortized cost basis of the hedged commercial loans was $37,071,000 and the cumulative basis adjustment associated with the hedging relationships was $(2,535,000). (In thousands) September 30, 2022 Balance sheet line item in which hedged item is recorded Carrying value of hedged items Cumulative gain (loss) fair value hedge adjustment included in carrying amount of hedged items Loans receivable (1) (2) $ 1,159,496 $ (39,090) $ 1,159,496 $ (39,090) (1) Includes the amortized cost basis of the closed mortgage loan portfolios used to designate the hedging relationships in which the hedged items are the last layer expected to be remaining at the end of the hedging relationships. At September 30, 2022, the amortized cost basis of the closed loan portfolios used in the hedging relationships was $1,119,975,000, the cumulative basis adjustment associated with the hedging relationships was $(36,458,000), and the amount of the designated hedged items was $470,000,000. (2) Includes the amortized cost basis of commercial loans designated in fair value hedging relationships. At September 30, 2022, the amortized cost basis of the hedged commercial loans was $39,521,000 and the cumulative basis adjustment associated with the hedging relationships was $(2,632,000). The Company has entered into interest rate swaps to convert certain short-term borrowings to fixed rate payments. The primary purpose of these hedges is to mitigate the risk of changes in future cash flows resulting from increasing interest rates. For qualifying cash flow hedges under ASC 815, gains and losses on the interest rate swaps are recorded in accumulated other comprehensive income ("AOCI") and then reclassified into earnings in the same period the hedged cash flows affect earnings and within the same income statement line item as the hedged cash flows. As of December 31, 2022, the maturities for hedges of adjustable rate borrowings ranged from two years to eight years, with the weighted average being 6.3 years. The following table presents the impact of derivative instruments (cash flow hedges on borrowings) on AOCI for the periods presented. (In thousands) Three Months Ended December 31, Amount of gain/(loss) recognized in AOCI on derivatives in cash flow hedging relationships 2022 2021 Interest rate contracts: Pay fixed/receive floating swaps on borrowings cash flow hedges $ (6,806) $ 6,446 Total pre-tax gain/(loss) recognized in AOCI $ (6,806) $ 6,446 The following tables present the gain (loss) on derivative instruments in fair value and cash flow accounting hedging relationships under ASC 815 for the periods presented. Three Months Ended December 31, 2022 Three Months Ended December 31, 2021 Interest income on loans receivable Interest expense on FHLB advances Interest income on loans receivable Interest expense on FHLB advances (In thousands) (In thousands) Interest income/(expense), including the effects of fair value and cash flow hedges $ 203,946 $ (18,974) $ 138,509 $ (7,843) Gain/(loss) on fair value hedging relationships: Interest rate contracts Amounts related to interest settlements on derivatives $ 3,167 $ (1,371) Recognized on derivatives (2,849) 4,500 Recognized on hedged items 3,132 (4,475) Net income/(expense) recognized on fair value hedges $ 3,450 $ (1,346) Gain/(loss) on cash flow hedging relationships: Interest rate contracts Amounts related to interest settlements on derivatives $ 7,274 $ 2,021 Amount of derivative gain/(loss) reclassified from AOCI into interest income/expense — — Net income/(expense) recognized on cash flow hedges $ 7,274 $ 2,021 The Company periodically enters into certain interest rate swap agreements in order to provide commercial loan customers the ability to convert from variable to fixed interest rate payments, while the Company retains a variable rate loan. Under these agreements, the Company enters into a variable rate loan agreement and a swap agreement with the client. The swap agreement effectively converts the client’s variable rate loan into a fixed rate. The Company enters into a corresponding swap agreement with a third party in order to offset its exposure on the variable and fixed components of the client's swap agreement. The interest rate swaps are derivatives under ASC 815, with changes in fair value recorded in earnings. There was no net impact to the statement of operations for the three months ended December 31, 2022 and 2021 as the changes in fair value of the receive fixed swap and pay fixed swap offset each other. The following tables present the impact of derivative instruments (client swap program) that are not designated in accounting hedges under ASC 815 for the periods presented. (In thousands) Three Months Ended December 31, Derivative instruments Classification of gain/(loss) recognized in income on derivative instrument 2022 2021 Interest rate contracts: Pay fixed/receive floating swap Other noninterest income $ (3,878) $ 5,039 Receive fixed/pay floating swap Other noninterest income 3,878 (5,039) $ — $ —

Revenue from Contracts with Cus

Revenue from Contracts with Customers	3 Months Ended
	Dec. 31, 2022
Revenue from Contract with Customer [Abstract]
Revenue from Contracts with Customers	Revenue from Contracts with Customers Since net interest income on financial assets and liabilities is outside the scope of ASU No. 2014-09, Revenue from Contracts with Customers ("ASC 606"), a significant majority of our revenues are not subject to that guidance. Revenue streams that are within the scope of ASC 606 are presented within non-interest income and are, in general, recognized as revenue at the same time the Company's obligation to the customer is satisfied. Most of the Company's customer contracts that are within the scope of the new guidance are cancelable by either party without penalty and are short-term in nature. These sources of revenue include depositor and other consumer and business banking fees, commission income, as well as debit and credit card interchange fees. In scope revenue streams represented approximately 3.9% of our total revenues for the three months ended December 31, 2022, compared to 5.6% for the three months ended December 31, 2021. As this standard is immaterial to our consolidated financial statements, the Company has omitted certain disclosures in ASC 606, including the disaggregation of revenue table. Sources of non-interest income within the scope of the guidance include the following: Deposit related and other service charges (recognized in Deposit fee income) - The Company's deposit accounts are governed by standardized contracts customary in the industry. Revenues are earned at a point in time or over time (monthly) from account maintenance fees and charges for specific transactions such as wire transfers, stop payment orders, overdrafts, debit card replacements, check orders and cashier’s checks. The Company’s performance obligation related to each of these fees is generally satisfied, and the related revenue recognized, at the time the service is provided (point in time or monthly). The Company is principal in each of these contracts. Debit and Credit Card Interchange Fees (recognized in Deposit fee income) - The Company receives interchange fees from the debit card or credit card payment network based on transactions involving debit or credit cards issued by the Company, generally measured as a percentage of the underlying transaction. Interchange fees from debit and credit card transactions are recognized as the transaction processing services are provided by the network. The Company acts as an agent in the card payment network arrangement, so the interchange fees are recorded net of any expenses paid to the principal (the card payment network in this case).

Commitment and Contingencies

Commitment and Contingencies	3 Months Ended
	Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Lease Commitments - The Company’s lease commitments consist primarily of real estate property for branches and office space under various non-cancellable operating leases that expire between 2023 and 2070. The majority of the leases contain renewal options and provisions for increases in rental rates based on a predetermined schedule or an agreed upon index. Financial Instruments with Off-Balance Sheet Risk - The only material off-balance-sheet credit exposures are unfunded loan commitments, which had a combined balance of $4,822,769,000 and $4,947,570,000 at December 31, 2022 and September 30, 2022, respectively. The reserve was $31,500,000 as of December 31, 2022, which is an decrease from $32,500,000 at September 30, 2022. See Note A "Summary of Significant Accounting Policies" for details regarding the reserve methodology. Legal Proceedings - The Company and its subsidiaries are from time to time defendants in and are threatened with various legal proceedings arising from regular business activities. Management, after consulting with legal counsel, is of the opinion that the ultimate liability, if any, resulting from these pending or threatened actions and proceedings will not have a material effect on the financial statements of the Company.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Dec. 31, 2022
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation - The Company has prepared the consolidated unaudited interim financial statements included in this report. All intercompany transactions and accounts have been eliminated in consolidation. The preparation of financial statements, in conformity with accounting principles generally accepted in the United States of America (“GAAP”), requires management to make estimates and assumptions that affect amounts reported in the financial statements. Actual results could differ from these estimates. In the opinion of management, all adjustments (consisting only of normal recurring adjustments) necessary for a fair presentation are reflected in the interim financial statements. The information included in this Form 10-Q should be read in conjunction with the financial statements and related notes in the Company's 2022 Annual Report on Form 10-K filed with the Securities and Exchange Commission ("SEC") on November 18, 2022 ("2022 Annual Financial Statements"). Interim results are not necessarily indicative of results for a full year.
Equity Securities	Equity Securities - The Company records equity securities within Other assets in its Consolidated Statements of Financial Condition. These equity investments are accounted for under different methods. • Low-income housing tax credit investments are accounted for under the proportional amortization method in accordance with Accounting Standards Update (“ASU”) 2014-01, Equity Method and Joint Ventures (Topic 323) . • For other equity investments where the Company has significant influence, the Company applies the equity method of accounting, which adjusts the carrying value of the investment to recognize a proportionate share of the financial results of the investment entity, regardless of whether any distribution is made. Any adjustments to the fair value of these investments are recorded in Other income in the Consolidated Statements of Operations. • For other equity investments where neither ASU 2014-01 nor the equity method of accounting is applicable, the Company applies the fair value adjustment method of ASU 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities (Subtopic 825-10) . Any adjustments to the fair value of these investments are recorded in Other income in the Consolidated Statements of Operations. Fair value is determined by reference to readily
Allowance for Credit Losses (Loans Receivable) and Allowance for Credit Losses (Held-to-Maturity Debt Securities)	Allowance for Credit Losses (Loans Receivable) - The Company maintains an allowance for credit losses (“ACL”) for the expected credit losses of the loan portfolio as well as unfunded loan commitments. The amount of ACL is based on ongoing, quarterly assessments by management. The current expected credit loss methodology (“CECL”) requires an estimate of the credit losses expected over the life of an exposure (or pool of exposures) and replaces the incurred loss methodology’s threshold that delayed the recognition of a credit loss until it was probable a loss event was incurred. The ACL consists of the allowance for loan losses and the reserve for unfunded commitments. The estimate of expected credit losses under the CECL methodology is based on relevant information about past events, current conditions, and reasonable and supportable forecasts that affect the collectability of the reported amounts. Historical loss experience is generally the starting point for estimating expected credit losses. We then consider whether the historical loss experience should be adjusted for asset-specific risk characteristics or current conditions at the reporting date that did not exist over the period that historical experience was based for each loan type. Finally, we consider forecasts about future economic conditions or changes in collateral values that are reasonable and supportable. Portfolio segment is defined as the level at which an entity develops and documents a systematic methodology to determine its ACL. The Company has designated two loan portfolio segments, commercial loans and consumer loans. These loan portfolio segments are further disaggregated into classes, which represent loans of similar type, risk characteristics, and methods for monitoring and assessing credit risk. The commercial loan portfolio segment is disaggregated into five classes: multi-family, commercial real estate, commercial and industrial, construction, and land acquisition and development. The risk of loss for the commercial loan portfolio segment is generally most indicated by the credit risk rating assigned to each borrower. Commercial loan risk ratings are determined by experienced senior credit officers based on specific facts and circumstances and are subject to periodic review by an independent internal team of credit specialists. The consumer loan portfolio segment is disaggregated into five classes: single-family-residential mortgage, custom construction, consumer lot loans, home equity lines of credit, and other consumer. The risk of loss for the consumer loan portfolio segment is generally most indicated by delinquency status and general economic factors. Each commercial and consumer loan portfolio class may also be further segmented based on risk characteristics. For most of our loan portfolio classes, the historical loss experience is determined using a cohort methodology. This method pools loans into groups (“cohorts”) sharing similar risk characteristics and tracks each cohort’s net charge-offs over the lives of the loans to calculate a historical loss rate. The historical loss rates for each cohort are then averaged to calculate an overall historical loss rate which is applied to the current loan balance to arrive at the quantitative baseline portion of the allowance for credit losses for the respective loan portfolio class. For certain loan portfolio classes, the Company determined there was not sufficient historical loss information to calculate a meaningful historical loss rate using the cohort methodology. For any such loan portfolio class, the weighted-average remaining maturity (“WARM”) methodology is being utilized until sufficient historical loss data is obtained. The WARM method multiplies an average annual loss rate by the expected remaining life of the loan pool to arrive at the quantitative baseline portion of the allowance for credit losses for the respective loan portfolio class. The Company also considers qualitative adjustments to the historical loss rate for each loan portfolio class. The qualitative adjustments for each loan class consider the conditions over the period from which historical loss experience was based and are split into two components: 1) asset or class specific risk characteristics or current conditions at the reporting date related to portfolio credit quality, remaining payments, volume and nature, credit culture and management, business environment or other management factors and 2) reasonable and supportable forecast of future economic conditions and collateral values. The Company performs a quarterly asset quality review which includes a review of forecasted gross charge-offs and recoveries, nonperforming assets, criticized loans, risk rating migration, delinquencies, etc. The asset quality review is performed by management and the results are used to consider a qualitative overlay to the quantitative baseline. The second qualitative adjustment noted above, economic conditions and collateral values, encompasses a one-year reasonable and supportable forecast period. The overlay adjustment for the reasonable and supportable forecast assumes an immediate reversion after the one-year forecast period to historical loss rates for the remaining life of the respective loan pool. When management deems it to be appropriate, the Company establishes a specific reserve for individually evaluated loans that do not share similar risk characteristics with the loans included in each respective loan pool. These individually evaluated loans are removed from their respective pools and typically represent collateral dependent loans but may also include other non-performing loans or troubled debt restructurings (“TDRs”). In addition, the Company individually evaluates “reasonably expected” TDRs, which are identified by the Company as a loan expected to be classified as a TDR within the next six months. Management judgment is utilized to make this determination. Allowance for Credit Losses (Held-to-Maturity Debt Securities) - For held-to-maturity (“HTM”) debt securities, the Company is required to utilize a CECL methodology to estimate expected credit losses. Substantially all of the Company’s HTM debt securities are issued by U.S. government agencies or U.S. government-sponsored enterprises. These securities carry the explicit and/or implicit guarantee of the U.S. government and have a long history of zero credit loss. See Note F "Fair Value Measurements" for more information about HTM debt securities.
Accrued Interest Receivable	Accrued Interest Receivable - The Company made the following elections regarding accrued interest receivable (“AIR”): • Presenting accrued interest receivable balances separately from their underlying instruments within the consolidated statements of financial condition. • Excluding accrued interest receivable that is included in the amortized cost of financing receivables from related disclosure requirements. • Continuing our policy to write off accrued interest receivable by reversing interest income in cases where the Company does not reasonably expect to receive payment. • Not measuring an allowance for credit losses for accrued interest receivable due to the Company’s policy of writing off uncollectible accrued interest receivable balances in a timely manner, as described above.
Non-Accrual and Collateral-Dependent Loans	Non-Accrual Loans - Loans are placed on non-accrual status when, in the judgment of management, the probability of collection of interest is deemed to be insufficient to warrant further accrual. When a loan is placed on non-accrual status, previously accrued but unpaid interest is deducted from interest income. The Bank does not accrue interest on loans 90 days or more past due. If payment is made on a loan so that the loan becomes less than 90 days past due, and the Bank expects full collection of principal and interest, the loan is returned to full accrual status. Any interest ultimately collected is credited to income in the period of recovery. A loan is charged-off when the loss is estimable and it is confirmed that the borrower is not expected to be able to meet contractual obligations. If a consumer loan is on non-accrual status before becoming a TDR it will stay on non-accrual status following restructuring until it has been performing for at least six months, at which point it may be moved to accrual status. If a loan is on accrual status before it becomes a TDR, and management concludes that full repayment is probable based on internal evaluation, it will remain on accrual status following restructuring. If the restructured consumer loan does not perform, it is placed on non-accrual status when it is 90 days delinquent. For commercial loans, six consecutive payments on newly restructured loan terms are required prior to returning the loan to accrual status. In some instances, after the required six consecutive payments are made, management will conclude that collection of the entire principal and interest due is still in doubt. In those instances, the loan will remain on non-accrual status. Collateral-Dependent Loans - A financial asset is considered collateral-dependent when the debtor is experiencing financial difficulty and repayment is expected to be provided substantially through the sale or operation of the collateral. For all classes of loans and leases deemed collateral-dependent, the Company elected the practical expedient to estimate expected credit losses based on the collateral’s fair value less cost to sell. In most cases, the Company records a partial charge-off to reduce the loan’s carrying value to the collateral’s fair value less cost to sell. Substantially all of the collateral consists of various types of real estate including residential properties; commercial properties such as retail centers, office buildings, and lodging; agriculture land; and vacant land.
Off-balance-sheet credit exposures	The reserve for unfunded commitments is recognized as a liability (other liabilities in the consolidated statements of financial condition), with adjustments to the reserve recognized through provision for credit losses in the consolidated statements of income. The reserve for unfunded commitments represents the expected lifetime credit losses on off-balance sheet obligations such as commitments to extend credit and standby letters of credit. However, a liability is not recognized for commitments that are unconditionally cancellable by the Company. The reserve for unfunded commitments is determined by estimating future draws, including the effects of risk mitigation actions, and applying the expected loss rates on those draws. Loss rates are estimated by utilizing the same loss rates calculated for the allowance for credit losses related to the respective loan portfolio class. See Note I “Commitments and Contingencies” for more information.
New Accounting Pronouncements	New Accounting Pronouncements In March 2020, the Financial Accounting Standards Board (“FASB”) issued ASU 2020-04, Reference Rate Reform (Topic 848). The amendments in this ASU provide temporary, optional guidance to ease the potential burden in accounting for reference rate reform. The ASU provides optional expedients and exceptions for applying GAAP to transactions affected by reference rate reform if certain criteria are met. The ASU primarily includes relief related to contract modifications and hedging relationships, as well as providing a one-time election for the sale or transfer of debt securities classified as held-to-maturity. This guidance is effective immediately and the amendments were originally to be applied prospectively through December 31, 2022. However, the FASB issued ASU 2022-06, deferring the sunset date to December 31, 2024. The Company has evaluated the regulatory requirements to cease the use of LIBOR and has put in place systems and capabilities for this purpose. The adoption of this ASU is not expected to have a material impact on the Company's consolidated financial statements. In March 2022, the FASB issued ASU 2022-01, Derivatives and Hedging (Topic 815) . The amendments in this ASU clarify the guidance on ASC 815 on fair value hedge accounting of interest rate risk for portfolios and financial assets. Among other things, the amended guidance establishes the "last-of-layer" method for making the fair value hedge accounting for these portfolios more accessible and renames that method the "portfolio layer" method. The amendments in this ASU are effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. We do not expect the amendments to have a material effect on our consolidated financial statements. In March 2022, the FASB issued ASU 2022-02, Financial Instruments - Credit Losses (Topic 326) . The amendments in this ASU eliminate the guidance on troubled debt restructurings while enhancing disclosure requirements for certain loan refinancing and restructurings by creditors made to borrowers experiencing financial difficulties. The ASU also requires that entities disclose current-period gross charge-offs by year of origination for loans and leases. The amendments in this ASU are effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. We do not expect the amendments to have a material effect on our consolidated financial statements.
Fair Value Measurements	FASB ASC 820, Fair Value Measurement ("ASC 820") defines fair value as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. ASC 820 also establishes a fair value hierarchy that requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The standard describes three levels of inputs that may be used to measure fair value: Level 1: Quoted prices (unadjusted) for identical assets or liabilities in active exchange markets that the entity has the ability to access as of the measurement date. Level 2: Significant other observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active and other inputs that are observable or can be corroborated by observable market data. Level 3: Significant unobservable inputs that reflect a company’s own assumptions about the assumptions that market participants would use in pricing an asset or liability. The Company has established and documented the process for determining the fair values of its assets and liabilities, where applicable. Fair value is based on quoted market prices, when available, for identical or similar assets or liabilities. In the absence of quoted market prices, fair value is determined using valuation models or third-party appraisals. The following is a description of the valuation methodologies used to measure and report the fair value of financial assets and liabilities on a recurring or nonrecurring basis. Measured on a Recurring Basis Available-for-Sale Securities and Derivative Contracts Securities available for sale are recorded at fair value on a recurring basis. The fair value of debt securities are priced using model pricing based on the securities' relationship to other benchmark quoted prices as provided by an independent third party, and under GAAP are considered a Level 2 input method. Securities that are traded on active exchanges are measured using the closing price in an active market and are considered a Level 1 input method. The Company offers interest rate swaps to its variable rate borrowers who want to manage their interest rate risk. At the same time, the Company enters into the opposite trade with a counter party to offset its interest rate risk. The Company has also entered into commercial loan hedges, mortgage pool hedges and borrowings hedges using interest rate swaps. The fair value of these interest rate swaps are estimated by a third-party pricing service using a discounted cash flow technique. These are considered a Level 2 input method.

Loans Receivable (Tables)

Loans Receivable (Tables)	3 Months Ended
	Dec. 31, 2022
Receivables [Abstract]
Schedule of Loans Receivable	The following table is a summary of loans receivable by loan portfolio segment and class. December 31, 2022 September 30, 2022 (In thousands) (In thousands) Commercial loans Multi-family $ 2,713,331 13.4 % $ 2,645,801 13.7 % Commercial real estate 3,237,073 16.0 3,133,660 16.2 Commercial & industrial 2,628,131 13.0 2,350,984 12.1 Construction 4,055,474 20.0 3,784,388 19.5 Land - acquisition & development 253,682 1.2 291,301 1.5 Total commercial loans 12,887,691 63.6 12,206,134 63.0 Consumer loans Single-family residential 6,013,410 29.7 5,771,862 29.8 Construction - custom 926,126 4.6 974,652 5.0 Land - consumer lot loans 148,246 0.7 153,240 0.8 HELOC 212,123 1.0 203,528 1.0 Consumer 73,115 0.4 75,543 0.4 Total consumer loans 7,373,020 36.4 7,178,825 37.0 Total gross loans 20,260,711 100 % 19,384,959 100 % Less: Allowance for credit losses on loans 176,797 172,808 Loans in process 2,997,839 3,006,023 Net deferred fees, costs and discounts 92,487 92,564 Total loan contra accounts 3,267,123 3,271,395 Net loans $ 16,993,588 $ 16,113,564
Non-accrual Loans and Loans 90 Days or More Past Due and Accruing	The following table sets forth the amortized cost basis of non-accrual loans and loans 90 days or more past due and accruing. December 31, 2022 September 30, 2022 (In thousands, except ratio data) Non-accrual Non-accrual with no ACL 90 days or more past due and accruing Non-accrual Non-accrual with no ACL 90 days or more past due and accruing Commercial loans Multi-family $ 5,879 $ — $ — $ 5,912 $ — $ — Commercial real estate 4,635 — — 4,691 — — Commercial & industrial 906 906 — 5,693 1,308 — Construction — — — — — — Land - acquisition & development — — — — — — Total commercial loans 11,420 906 — 16,296 1,308 — Consumer loans Single-family residential 17,084 — — 17,450 — — Construction - custom 435 — — 435 — — Land - consumer lot loans 71 — — 84 — — HELOC 134 — — 233 — — Consumer 36 — — 36 — — Total consumer loans 17,760 — — 18,238 — — Total non-accrual loans $ 29,180 $ 906 $ — $ 34,534 $ 1,308 $ — % of total loans 0.17 % 0.21 %
Loan Delinquencies by Loan Portfolio and Class	The following tables provide details regarding loan delinquencies by loan portfolio and class. December 31, 2022 Days Delinquent Based on $ Amount of Loans % based Type of Loan Loans Receivable (Amortized Cost) Current 30 60 90 Total Delinquent (In thousands, except ratio data) Commercial Loans Multi-family $ 2,695,759 $ 2,695,759 $ — $ — $ — $ — — % Commercial real estate 3,213,308 3,212,259 533 452 64 1,049 0.03 Commercial & industrial 2,621,266 2,620,020 261 81 904 1,246 0.05 Construction 1,637,499 1,636,565 934 — 934 0.06 Land - acquisition & development 191,162 191,162 — — — — — Total commercial loans 10,358,994 10,355,765 1,728 533 968 3,229 0.03 Consumer Loans Single-family residential 5,967,678 5,946,382 5,661 2,038 13,597 21,296 0.36 Construction - custom 408,563 408,128 — — 435 435 0.11 Land - consumer lot loans 147,078 146,969 49 — 60 109 0.07 HELOC 214,904 212,655 2,121 — 128 2,249 1.05 Consumer 73,168 72,777 54 174 163 391 0.53 Total consumer loans 6,811,391 6,786,911 7,885 2,212 14,383 24,480 0.36 Total Loans $ 17,170,385 $ 17,142,676 $ 9,613 $ 2,745 $ 15,351 $ 27,709 0.16 % Delinquency % 99.84% 0.06% 0.01% 0.09% 0.16% September 30, 2022 Days Delinquent Based on $ Amount of Loans % based Type of Loan Loans Receivable (Amortized Cost) Current 30 60 90 Total Delinquent (In thousands, except ratio data) Commercial Loans Multi-family $ 2,626,479 $ 2,626,479 $ — $ — $ — $ — — % Commercial real estate 3,111,112 3,110,056 538 450 68 1,056 0.03 Commercial & industrial 2,343,403 2,336,791 — 919 5,693 6,612 0.28 Construction 1,423,891 1,423,891 — — — — Land - acquisition & development 223,616 223,616 — — — — — Total commercial loans 9,728,501 9,720,833 538 1,369 5,761 7,668 0.08 Consumer Loans Single-family residential 5,726,979 5,708,996 2,796 1,316 13,871 17,983 0.31 Construction - custom 397,343 396,908 — — 435 435 0.11 Land - consumer lot loans 151,945 151,746 — 139 60 199 0.13 HELOC 206,033 205,605 155 46 227 428 0.21 Consumer 75,571 75,357 162 17 35 214 0.28 Total consumer loans 6,557,871 6,538,612 3,113 1,518 14,628 19,259 0.29 Total Loans $ 16,286,372 $ 16,259,445 $ 3,651 $ 2,887 $ 20,389 $ 26,927 0.17 % Delinquency % 99.83% 0.02% 0.02% 0.13% 0.17%
Summary of Loans Based on Credit Quality Indicators	The following tables present by primary credit quality indicator, loan class, and year of origination, the amortized cost basis of loans receivable as of December 31, 2022 and September 30, 2022. December 31, 2022 Term Loans Amortized Cost Basis by Origination Year YTD 2023 2022 2021 2020 2019 Prior to 2019 Revolving Loans Revolving to Term Loans Total Loans Commercial loans Multi-family Pass $ 94,649 $ 666,795 $ 763,102 $ 486,468 $ 167,495 $ 464,692 $ 36,361 $ — $ 2,679,562 Substandard — 3,931 — 4,180 — 8,086 — — 16,197 Total $ 94,649 $ 670,726 $ 763,102 $ 490,648 $ 167,495 $ 472,778 $ 36,361 $ — $ 2,695,759 Commercial real estate Pass $ 130,440 $ 806,478 $ 722,298 $ 467,416 $ 296,176 $ 705,610 $ 1,375 $ — $ 3,129,793 Special Mention — — — — 1,382 — — — 1,382 Substandard — 5,562 1,584 26,609 30,517 15,291 2,570 — 82,133 Total $ 130,440 $ 812,040 $ 723,882 $ 494,025 $ 328,075 $ 720,901 $ 3,945 $ — $ 3,213,308 Commercial & industrial Pass $ 124,523 $ 272,160 $ 345,166 $ 134,933 $ 34,585 $ 211,323 $ 1,350,779 $ 1,911 $ 2,475,380 Special Mention — — 2,601 — — — 2,850 — 5,451 Substandard — 7,961 12,829 5,292 4,671 25,427 84,255 — 140,435 Total $ 124,523 $ 280,121 $ 360,596 $ 140,225 $ 39,256 $ 236,750 $ 1,437,884 $ 1,911 $ 2,621,266 Construction Pass $ 17,955 $ 651,808 $ 694,514 $ 155,086 $ 33,585 $ 375 $ 75,930 $ — $ 1,629,253 Substandard — 5,987 2,259 — — — — — 8,246 Total $ 17,955 $ 657,795 $ 696,773 $ 155,086 $ 33,585 $ 375 $ 75,930 $ — $ 1,637,499 Land - acquisition & development Pass $ 4,682 $ 88,588 $ 48,857 $ 17,530 $ 2,981 $ 25,932 $ 2,592 $ — $ 191,162 Total $ 4,682 $ 88,588 $ 48,857 $ 17,530 $ 2,981 $ 25,932 $ 2,592 $ — $ 191,162 Total commercial loans Pass $ 372,249 $ 2,485,829 $ 2,573,937 $ 1,261,433 $ 534,822 $ 1,407,932 $ 1,467,037 $ 1,911 $ 10,105,150 Special Mention — — 2,601 — 1,382 — 2,850 — 6,833 Substandard — 23,441 16,672 36,081 35,188 48,804 86,825 — 247,011 Total $ 372,249 $ 2,509,270 $ 2,593,210 $ 1,297,514 $ 571,392 $ 1,456,736 $ 1,556,712 $ 1,911 $ 10,358,994 December 31, 2022 Term Loans Amortized Cost Basis by Origination Year YTD 2023 2022 2021 2020 2019 Prior to 2019 Revolving Loans Revolving to Term Loans Total Loans Consumer loans Single-family residential Current $ 219,679 $ 1,148,027 $ 1,717,690 $ 768,368 $ 313,719 $ 1,778,899 $ — $ — $ 5,946,382 30 days past due — — 1,637 — 63 3,961 — — 5,661 60 days past due — — — — — 2,038 — — 2,038 90+ days past due — — — — 1,084 12,513 — — 13,597 Total $ 219,679 $ 1,148,027 $ 1,719,327 $ 768,368 $ 314,866 $ 1,797,411 $ — $ — $ 5,967,678 Construction - custom Current $ — $ 320,079 $ 82,349 $ 4,864 $ 358 $ 478 $ — $ — $ 408,128 90+ days past due — — 435 — — — — — 435 Total $ — $ 320,079 $ 82,784 $ 4,864 $ 358 $ 478 $ — $ — $ 408,563 Land - consumer lot loans Current $ 4,355 $ 50,736 $ 55,658 $ 15,336 $ 5,189 $ 15,695 $ — $ — $ 146,969 30 days past due — — — — — 49 — — 49 90+ days past due — — — — — 60 — — 60 Total $ 4,355 $ 50,736 $ 55,658 $ 15,336 $ 5,189 $ 15,804 $ — $ — $ 147,078 HELOC Current $ — $ — $ — $ — $ — $ 4,846 $ 207,284 $ 525 $ 212,655 30 days past due — — — — — 260 1,861 — 2,121 90+ days past due — — — — — — 128 — 128 Total $ — $ — $ — $ — $ — $ 5,106 $ 209,273 $ 525 $ 214,904 Consumer Current $ 108 $ 2,145 $ 9,986 $ 8,023 $ 203 $ 28,303 $ 24,009 $ — $ 72,777 30 days past due — — — — — 37 17 — 54 60 days past due — — — — 1 173 — — 174 90+ days past due — 2 — — 32 129 — — 163 Total $ 108 $ 2,147 $ 9,986 $ 8,023 $ 236 $ 28,642 $ 24,026 $ — $ 73,168 Total consumer loans Current $ 224,142 $ 1,520,987 $ 1,865,683 $ 796,591 $ 319,469 $ 1,828,221 $ 231,293 $ 525 $ 6,786,911 30 days past due — — 1,637 — 63 4,307 1,878 — 7,885 60 days past due — — — — 1 2,211 — — 2,212 90+ days past due — 2 435 — 1,116 12,702 128 — 14,383 Total $ 224,142 $ 1,520,989 $ 1,867,755 $ 796,591 $ 320,649 $ 1,847,441 $ 233,299 $ 525 $ 6,811,391 The following tables provide the amortized cost of loans receivable based on risk rating categories as previously defined. December 31, 2022 Internally Assigned Grade Pass Special mention Substandard Doubtful Loss Total (In thousands, except ratio data) Loan type Commercial loans Multi-family $ 2,679,562 $ — $ 16,197 $ — $ — $ 2,695,759 Commercial real estate 3,129,793 1,382 82,133 — — 3,213,308 Commercial & industrial 2,475,380 5,451 140,435 — — 2,621,266 Construction 1,629,253 — 8,246 — — 1,637,499 Land - acquisition & development 191,162 — — — — 191,162 Total commercial loans 10,105,150 6,833 247,011 — — 10,358,994 Consumer loans Single-family residential 5,947,295 — 20,383 — — 5,967,678 Construction - custom 408,127 — 436 — — 408,563 Land - consumer lot loans 147,007 — 71 — — 147,078 HELOC 214,771 — 133 — — 214,904 Consumer 73,161 — 7 — — 73,168 Total consumer loans 6,790,361 — 21,030 — — 6,811,391 Total $ 16,895,511 $ 6,833 $ 268,041 $ — $ — $ 17,170,385 Total grade as a % of total loans 98.40 % 0.04 % 1.56 % — % — % September 30, 2022 Internally Assigned Grade Pass Special mention Substandard Doubtful Loss Total Gross Loans (In thousands, except ratio data) Loan type Commercial loans Multi-family $ 2,612,669 $ — $ 13,810 $ — $ — $ 2,626,479 Commercial real estate 3,054,241 1,594 55,277 — — 3,111,112 Commercial & industrial 2,196,767 31,656 114,980 — — 2,343,403 Construction 1,421,634 — 2,257 — — 1,423,891 Land - acquisition & development 223,616 — — — — 223,616 Total commercial loans 9,508,927 33,250 186,324 — — 9,728,501 Consumer loans Single-family residential 5,706,199 — 20,780 — — 5,726,979 Construction - custom 396,908 — 435 — — 397,343 Land - consumer lot loans 151,723 — 222 — — 151,945 HELOC 205,800 — 233 — — 206,033 Consumer 75,570 — 1 — — 75,571 Total consumer loans 6,536,200 — 21,671 — — 6,557,871 Total loans $ 16,045,127 $ 33,250 $ 207,995 $ — $ — $ 16,286,372 Total grade as a % of total gross loans 98.52 % 0.20 % 1.28 % — % — % The following tables provide information on amortized cost of loans receivable based on borrower payment activity. December 31, 2022 Performing Loans Non-Performing Loans Amount % of Total Amount % of Total (In thousands, except ratio data) Commercial loans Multi-family $ 2,689,880 99.8 % $ 5,879 0.2 % Commercial real estate 3,208,673 99.9 4,635 0.1 Commercial & industrial 2,620,360 100.0 906 — Construction 1,637,499 100.0 — 0.0 Land - acquisition & development 191,162 100.0 — — Total commercial loans 10,347,574 99.9 11,420 0.1 Consumer loans Single-family residential 5,950,594 99.7 17,084 0.3 Construction - custom 408,128 99.9 435 0.1 Land - consumer lot loans 147,007 100.0 71 0.0 HELOC 214,770 99.9 134 0.1 Consumer 73,132 100.0 36 0.0 Total consumer loans 6,793,631 99.7 17,760 0.3 Total loans $ 17,141,205 99.8 % $ 29,180 0.2 % September 30, 2022 Performing Loans Non-Performing Loans Amount % of Total Amount % of Total (In thousands, except ratio data) Commercial loans Multi-family $ 2,620,567 99.8 % $ 5,912 0.2 % Commercial real estate 3,106,421 99.8 4,691 0.2 Commercial & industrial 2,337,710 99.8 5,693 0.2 Construction 1,423,891 100.0 — — Land - acquisition & development 223,616 100.0 — — Total commercial loans 9,712,205 99.8 16,296 0.2 Consumer loans Single-family residential 5,709,529 99.7 17,450 0.3 Construction - custom 396,908 99.9 435 0.1 Land - consumer lot loans 151,861 99.9 84 0.1 HELOC 205,800 99.9 233 0.1 Consumer 75,535 100.0 36 0.0 Total consumer loans 6,539,633 99.7 18,238 0.4 Total loans $ 16,251,838 99.8 % $ 34,534 0.2 %

Allowance for Losses on Loans (

Allowance for Losses on Loans (Tables)	3 Months Ended
	Dec. 31, 2022
Receivables [Abstract]
Allowance for Credit Losses by Loan Portfolio Segment and Class	The following tables summarize the activity in the allowance for loan losses by loan portfolio segment and class. Three Months Ended December 31, 2022 Beginning Allowance Charge-offs Recoveries Provision & Ending Allowance (In thousands) Commercial loans Multi-family $ 12,013 $ — $ — $ 311 $ 12,324 Commercial real estate 25,814 — 4 1,562 27,380 Commercial & industrial 57,210 (82) 32 6,713 63,873 Construction 26,161 — — (28) 26,133 Land - acquisition & development 12,278 — 16 (3,722) 8,572 Total commercial loans 133,476 (82) 52 4,836 138,282 Consumer loans Single-family residential 25,518 — 430 (473) 25,475 Construction - custom 3,410 — — 90 3,500 Land - consumer lot loans 5,047 — — (905) 4,142 HELOC 2,482 — 1 105 2,588 Consumer 2,875 (146) 234 (153) 2,810 Total consumer loans 39,332 (146) 665 (1,336) 38,515 Total ACL - loans $ 172,808 $ (228) $ 717 $ 3,500 $ 176,797 (1) Provision & transfer amounts within the table do not include provision recapture for unfunded commitments of $1,000,000. Three Months Ended December 31, 2021 Beginning Allowance Charge-offs Recoveries Provision & Transfers (1) Ending Allowance (In thousands) Commercial loans Multi-family $ 16,949 $ — $ — $ (956) $ 15,993 Commercial real estate 23,437 (529) 44 2,770 25,722 Commercial & industrial 45,957 (43) 62 1,255 47,231 Construction 25,585 — 2,000 (2,819) 24,766 Land - acquisition & development 13,447 (2) 20 660 14,125 Total commercial loans 125,375 (574) 2,126 910 127,837 Consumer loans Single-family residential 30,978 — 405 (1,277) 30,106 Construction - custom 4,907 — — (1,188) 3,719 Land - consumer lot loans 4,939 (27) 5 67 4,984 HELOC 2,390 — 1 (26) 2,365 Consumer 2,711 (76) 251 (486) 2,400 Total consumer loans 45,925 (103) 662 (2,910) 43,574 Total loans $ 171,300 $ (677) $ 2,788 $ (2,000) $ 171,411 (1) Provision & transfer amounts within the table do not include the provision for unfunded commitments of $2,500,000.
Summary of Loans Based on Credit Quality Indicators	The following tables present by primary credit quality indicator, loan class, and year of origination, the amortized cost basis of loans receivable as of December 31, 2022 and September 30, 2022. December 31, 2022 Term Loans Amortized Cost Basis by Origination Year YTD 2023 2022 2021 2020 2019 Prior to 2019 Revolving Loans Revolving to Term Loans Total Loans Commercial loans Multi-family Pass $ 94,649 $ 666,795 $ 763,102 $ 486,468 $ 167,495 $ 464,692 $ 36,361 $ — $ 2,679,562 Substandard — 3,931 — 4,180 — 8,086 — — 16,197 Total $ 94,649 $ 670,726 $ 763,102 $ 490,648 $ 167,495 $ 472,778 $ 36,361 $ — $ 2,695,759 Commercial real estate Pass $ 130,440 $ 806,478 $ 722,298 $ 467,416 $ 296,176 $ 705,610 $ 1,375 $ — $ 3,129,793 Special Mention — — — — 1,382 — — — 1,382 Substandard — 5,562 1,584 26,609 30,517 15,291 2,570 — 82,133 Total $ 130,440 $ 812,040 $ 723,882 $ 494,025 $ 328,075 $ 720,901 $ 3,945 $ — $ 3,213,308 Commercial & industrial Pass $ 124,523 $ 272,160 $ 345,166 $ 134,933 $ 34,585 $ 211,323 $ 1,350,779 $ 1,911 $ 2,475,380 Special Mention — — 2,601 — — — 2,850 — 5,451 Substandard — 7,961 12,829 5,292 4,671 25,427 84,255 — 140,435 Total $ 124,523 $ 280,121 $ 360,596 $ 140,225 $ 39,256 $ 236,750 $ 1,437,884 $ 1,911 $ 2,621,266 Construction Pass $ 17,955 $ 651,808 $ 694,514 $ 155,086 $ 33,585 $ 375 $ 75,930 $ — $ 1,629,253 Substandard — 5,987 2,259 — — — — — 8,246 Total $ 17,955 $ 657,795 $ 696,773 $ 155,086 $ 33,585 $ 375 $ 75,930 $ — $ 1,637,499 Land - acquisition & development Pass $ 4,682 $ 88,588 $ 48,857 $ 17,530 $ 2,981 $ 25,932 $ 2,592 $ — $ 191,162 Total $ 4,682 $ 88,588 $ 48,857 $ 17,530 $ 2,981 $ 25,932 $ 2,592 $ — $ 191,162 Total commercial loans Pass $ 372,249 $ 2,485,829 $ 2,573,937 $ 1,261,433 $ 534,822 $ 1,407,932 $ 1,467,037 $ 1,911 $ 10,105,150 Special Mention — — 2,601 — 1,382 — 2,850 — 6,833 Substandard — 23,441 16,672 36,081 35,188 48,804 86,825 — 247,011 Total $ 372,249 $ 2,509,270 $ 2,593,210 $ 1,297,514 $ 571,392 $ 1,456,736 $ 1,556,712 $ 1,911 $ 10,358,994 December 31, 2022 Term Loans Amortized Cost Basis by Origination Year YTD 2023 2022 2021 2020 2019 Prior to 2019 Revolving Loans Revolving to Term Loans Total Loans Consumer loans Single-family residential Current $ 219,679 $ 1,148,027 $ 1,717,690 $ 768,368 $ 313,719 $ 1,778,899 $ — $ — $ 5,946,382 30 days past due — — 1,637 — 63 3,961 — — 5,661 60 days past due — — — — — 2,038 — — 2,038 90+ days past due — — — — 1,084 12,513 — — 13,597 Total $ 219,679 $ 1,148,027 $ 1,719,327 $ 768,368 $ 314,866 $ 1,797,411 $ — $ — $ 5,967,678 Construction - custom Current $ — $ 320,079 $ 82,349 $ 4,864 $ 358 $ 478 $ — $ — $ 408,128 90+ days past due — — 435 — — — — — 435 Total $ — $ 320,079 $ 82,784 $ 4,864 $ 358 $ 478 $ — $ — $ 408,563 Land - consumer lot loans Current $ 4,355 $ 50,736 $ 55,658 $ 15,336 $ 5,189 $ 15,695 $ — $ — $ 146,969 30 days past due — — — — — 49 — — 49 90+ days past due — — — — — 60 — — 60 Total $ 4,355 $ 50,736 $ 55,658 $ 15,336 $ 5,189 $ 15,804 $ — $ — $ 147,078 HELOC Current $ — $ — $ — $ — $ — $ 4,846 $ 207,284 $ 525 $ 212,655 30 days past due — — — — — 260 1,861 — 2,121 90+ days past due — — — — — — 128 — 128 Total $ — $ — $ — $ — $ — $ 5,106 $ 209,273 $ 525 $ 214,904 Consumer Current $ 108 $ 2,145 $ 9,986 $ 8,023 $ 203 $ 28,303 $ 24,009 $ — $ 72,777 30 days past due — — — — — 37 17 — 54 60 days past due — — — — 1 173 — — 174 90+ days past due — 2 — — 32 129 — — 163 Total $ 108 $ 2,147 $ 9,986 $ 8,023 $ 236 $ 28,642 $ 24,026 $ — $ 73,168 Total consumer loans Current $ 224,142 $ 1,520,987 $ 1,865,683 $ 796,591 $ 319,469 $ 1,828,221 $ 231,293 $ 525 $ 6,786,911 30 days past due — — 1,637 — 63 4,307 1,878 — 7,885 60 days past due — — — — 1 2,211 — — 2,212 90+ days past due — 2 435 — 1,116 12,702 128 — 14,383 Total $ 224,142 $ 1,520,989 $ 1,867,755 $ 796,591 $ 320,649 $ 1,847,441 $ 233,299 $ 525 $ 6,811,391 The following tables provide the amortized cost of loans receivable based on risk rating categories as previously defined. December 31, 2022 Internally Assigned Grade Pass Special mention Substandard Doubtful Loss Total (In thousands, except ratio data) Loan type Commercial loans Multi-family $ 2,679,562 $ — $ 16,197 $ — $ — $ 2,695,759 Commercial real estate 3,129,793 1,382 82,133 — — 3,213,308 Commercial & industrial 2,475,380 5,451 140,435 — — 2,621,266 Construction 1,629,253 — 8,246 — — 1,637,499 Land - acquisition & development 191,162 — — — — 191,162 Total commercial loans 10,105,150 6,833 247,011 — — 10,358,994 Consumer loans Single-family residential 5,947,295 — 20,383 — — 5,967,678 Construction - custom 408,127 — 436 — — 408,563 Land - consumer lot loans 147,007 — 71 — — 147,078 HELOC 214,771 — 133 — — 214,904 Consumer 73,161 — 7 — — 73,168 Total consumer loans 6,790,361 — 21,030 — — 6,811,391 Total $ 16,895,511 $ 6,833 $ 268,041 $ — $ — $ 17,170,385 Total grade as a % of total loans 98.40 % 0.04 % 1.56 % — % — % September 30, 2022 Internally Assigned Grade Pass Special mention Substandard Doubtful Loss Total Gross Loans (In thousands, except ratio data) Loan type Commercial loans Multi-family $ 2,612,669 $ — $ 13,810 $ — $ — $ 2,626,479 Commercial real estate 3,054,241 1,594 55,277 — — 3,111,112 Commercial & industrial 2,196,767 31,656 114,980 — — 2,343,403 Construction 1,421,634 — 2,257 — — 1,423,891 Land - acquisition & development 223,616 — — — — 223,616 Total commercial loans 9,508,927 33,250 186,324 — — 9,728,501 Consumer loans Single-family residential 5,706,199 — 20,780 — — 5,726,979 Construction - custom 396,908 — 435 — — 397,343 Land - consumer lot loans 151,723 — 222 — — 151,945 HELOC 205,800 — 233 — — 206,033 Consumer 75,570 — 1 — — 75,571 Total consumer loans 6,536,200 — 21,671 — — 6,557,871 Total loans $ 16,045,127 $ 33,250 $ 207,995 $ — $ — $ 16,286,372 Total grade as a % of total gross loans 98.52 % 0.20 % 1.28 % — % — % The following tables provide information on amortized cost of loans receivable based on borrower payment activity. December 31, 2022 Performing Loans Non-Performing Loans Amount % of Total Amount % of Total (In thousands, except ratio data) Commercial loans Multi-family $ 2,689,880 99.8 % $ 5,879 0.2 % Commercial real estate 3,208,673 99.9 4,635 0.1 Commercial & industrial 2,620,360 100.0 906 — Construction 1,637,499 100.0 — 0.0 Land - acquisition & development 191,162 100.0 — — Total commercial loans 10,347,574 99.9 11,420 0.1 Consumer loans Single-family residential 5,950,594 99.7 17,084 0.3 Construction - custom 408,128 99.9 435 0.1 Land - consumer lot loans 147,007 100.0 71 0.0 HELOC 214,770 99.9 134 0.1 Consumer 73,132 100.0 36 0.0 Total consumer loans 6,793,631 99.7 17,760 0.3 Total loans $ 17,141,205 99.8 % $ 29,180 0.2 % September 30, 2022 Performing Loans Non-Performing Loans Amount % of Total Amount % of Total (In thousands, except ratio data) Commercial loans Multi-family $ 2,620,567 99.8 % $ 5,912 0.2 % Commercial real estate 3,106,421 99.8 4,691 0.2 Commercial & industrial 2,337,710 99.8 5,693 0.2 Construction 1,423,891 100.0 — — Land - acquisition & development 223,616 100.0 — — Total commercial loans 9,712,205 99.8 16,296 0.2 Consumer loans Single-family residential 5,709,529 99.7 17,450 0.3 Construction - custom 396,908 99.9 435 0.1 Land - consumer lot loans 151,861 99.9 84 0.1 HELOC 205,800 99.9 233 0.1 Consumer 75,535 100.0 36 0.0 Total consumer loans 6,539,633 99.7 18,238 0.4 Total loans $ 16,251,838 99.8 % $ 34,534 0.2 %

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Dec. 31, 2022
Fair Value Disclosures [Abstract]
Fair Value of Assets Measured on Recurring Basis	The following tables present the balance and level in the fair value hierarchy of assets and liabilities that are measured at fair value on a recurring basis. December 31, 2022 Level 1 Level 2 Level 3 Total (In thousands) Financial Assets Available-for-sale securities: U.S. government and agency securities $ — $ 99,889 $ — $ 99,889 Asset-backed securities — 696,572 — 696,572 Municipal bonds — 35,054 — 35,054 Corporate debt securities — 316,487 — 316,487 Mortgage-backed securities Agency pass-through certificates — 911,835 — 911,835 Total available-for-sale securities — 2,059,837 — 2,059,837 Client swap program hedges — 63,383 — 63,383 Commercial loan fair value hedges — 2,446 — 2,446 Mortgage loan fair value hedges — 33,986 — 33,986 Borrowings cash flow hedges — 173,139 — 173,139 Total financial assets $ — $ 2,332,791 $ — $ 2,332,791 Financial Liabilities Client swap program hedges $ — $ 63,383 $ — $ 63,383 Total financial liabilities $ — $ 63,383 $ — $ 63,383 September 30, 2022 Level 1 Level 2 Level 3 Total (In thousands) Financial Assets Available-for-sale securities: U.S. government and agency securities $ — $ 39,354 $ — $ 39,354 Asset-backed securities — 767,001 767,001 Municipal bonds — 34,962 — 34,962 Corporate debt securities — 313,757 — 313,757 Mortgage-backed securities Agency pass-through certificates — 895,963 — 895,963 Total available-for-sale securities — 2,051,037 — 2,051,037 Client swap program hedges — 67,260 — 67,260 Commercial loan fair value hedges — 2,517 — 2,517 Mortgage loan fair value hedges — 36,765 — 36,765 Borrowings cash flow hedges — 179,945 — 179,945 Total financial assets $ — $ 2,337,524 $ — $ 2,337,524 Financial Liabilities Client swap program hedges $ — $ 67,260 $ — $ 67,260 Total financial liabilities $ — $ 67,260 $ — $ 67,260
Fair Value of Assets Measured on Nonrecurring Basis	The following tables present the aggregated balance of assets that were measured at fair value on a nonrecurring basis at December 31, 2022 and December 31, 2021, and the total gains (losses) resulting from those fair value adjustments during the respective periods. The estimated fair value measurements are shown gross of estimated selling costs. December 31, 2022 Three Months Ended December 31, 2022 Level 1 Level 2 Level 3 Total Total Gains (Losses) (In thousands) (In thousands) Loans (1) $ — $ — $ — $ — $ (123) Real estate owned (2) — — — — — Balance at end of period $ — $ — $ — $ — $ (123) (1) The gains (losses) represent re-measurements of collateral-dependent loans. (2) The gains (losses) represent aggregate write-downs and charge-offs on real estate owned. December 31, 2021 Three Months Ended December 31, 2021 Level 1 Level 2 Level 3 Total Total Gains (Losses) (In thousands) (In thousands) Loans (1) $ — $ — $ 202 $ 202 $ (89) Real estate owned (2) — — 1,390 1,390 (504) Balance at end of period $ — $ — $ 1,592 $ 1,592 $ (593) (1) The gains (losses) represent re-measurements of collateral-dependent loans. (2) The gains (losses) represent aggregate write-downs and charge-offs on real estate owned.
Fair Value of Financial Instruments by Balance Sheet Grouping	Although management is not aware of any factors that would materially affect the estimated fair value amounts presented below, such amounts have not been comprehensively revalued for purposes of these financial statements since the dates shown, and therefore, estimates of fair value subsequent to those dates may differ significantly from the amounts presented below. December 31, 2022 September 30, 2022 Level in Fair Value Hierarchy Carrying Estimated Carrying Estimated ($ in thousands) Financial assets Cash and cash equivalents 1 $ 645,862 $ 645,862 $ 683,965 $ 683,965 Available-for-sale securities U.S. government and agency securities 2 99,889 99,889 39,354 39,354 Asset-backed securities 2 696,572 696,572 767,001 767,001 Municipal bonds 2 35,054 35,054 34,962 34,962 Corporate debt securities 2 316,487 316,487 313,757 313,757 Mortgage-backed securities Agency pass-through certificates 2 911,835 911,835 895,963 895,963 Total available-for-sale securities 2,059,837 2,059,837 2,051,037 2,051,037 Held-to-maturity securities Mortgage-backed securities Agency pass-through certificates 2 453,443 402,055 463,299 406,860 Total held-to-maturity securities 453,443 402,055 463,299 406,860 Loans receivable 3 16,993,588 16,310,687 16,113,564 15,417,635 FHLB and FRB stock 2 133,073 133,073 95,073 95,073 Other assets - client swap program hedges 2 63,383 63,383 67,260 67,260 Other assets - commercial fair value loan hedges 2 2,446 2,446 2,517 2,517 Other assets - mortgage loan fair value hedges 2 33,986 33,986 36,765 36,765 Other assets - borrowings cash flow hedges 2 173,139 173,139 179,945 179,945 Financial liabilities Time deposits 2 3,412,203 3,329,708 3,338,043 3,249,169 FHLB advances 2 3,075,000 3,067,487 2,125,000 1,940,813 Other liabilities - client swap program hedges 2 63,383 63,383 67,260 67,260
Reconciliation of Amortized Cost to Fair Value of Available-for-Sale and Held-to-Maturity Securities	The following tables provide details about the amortized cost and fair value of available-for-sale and held-to-maturity securities. December 31, 2022 Amortized Gross Unrealized Fair Yield Gains Losses ($ in thousands) Available-for-sale securities U.S. government and agency securities due 1 to 5 years $ 36,531 $ — $ (925) $ 35,606 4.33 % Over 10 years 64,060 223 — 64,283 3.90 Asset-backed securities 1 to 5 years 21,033 — (1,524) 19,509 4.58 5 to 10 years 67,783 — (1,025) 66,758 5.01 Over 10 years 627,579 365 (17,639) 610,305 5.12 Corporate debt securities due Within 1 year 75,000 29 (212) 74,817 5.08 1 to 5 years 151,531 232 (3,435) 148,328 4.49 5 to 10 years 114,116 — (20,774) 93,342 3.87 Municipal bonds due 5 to 10 years 5,743 — (360) 5,383 3.00 Over 10 years 29,861 350 (540) 29,671 5.85 Mortgage-backed securities Agency pass-through certificates 985,480 11 (73,656) 911,835 2.98 2,178,717 1,210 (120,090) 2,059,837 3.99 Held-to-maturity securities Mortgage-backed securities Agency pass-through certificates 453,443 23 (51,411) 402,055 2.88 453,443 23 (51,411) 402,055 2.88 $ 2,632,160 $ 1,233 $ (171,501) $ 2,461,892 3.80 % September 30, 2022 Amortized Gross Unrealized Fair Yield Gains Losses ($ in thousands) Available-for-sale securities U.S. government and agency securities due 1 to 5 years $ 40,403 $ — $ (1,049) $ 39,354 3.03 % Asset-backed securities 1 to 5 years 22,527 — (1,141) 21,386 3.27 5 to 10 years 82,962 4 (547) 82,419 3.53 Over 10 years 668,482 783 (6,069) 663,196 3.86 Corporate debt securities due Within 1 year 75,000 4 (200) 74,804 3.74 1 to 5 years 151,411 — (2,748) 148,663 3.59 5 to 10 years 114,414 — (24,124) 90,290 3.87 Municipal bonds due 5 to 10 years 5,751 — (361) 5,390 3.00 Over 10 years 29,871 400 (699) 29,572 5.85 Mortgage-backed securities Agency pass-through certificates 971,916 117 (76,070) 895,963 2.81 2,162,737 1,308 (113,008) 2,051,037 3.36 Held-to-maturity securities Mortgage-backed securities Agency pass-through certificates 463,299 22 (56,461) 406,860 2.88 463,299 22 (56,461) 406,860 2.88 $ 2,626,036 $ 1,330 $ (169,469) $ 2,457,897 3.28 %
Schedule of Debt Securities, Available-for-Sale	The following tables show the gross unrealized losses and fair value of securities as of December 31, 2022 and September 30, 2022, by length of time that individual securities in each category have been in a continuous loss position. There were 227 and 223 securities with an unrealized loss as of December 31, 2022 and September 30, 2022, respectively. The decline in fair value since purchase is attributable to changes in interest rates. Because the Company does not intend to sell these securities and does not consider it more likely than not that it will be required to sell these securities before the recovery of amortized cost basis, which may be upon maturity, the Company does not consider these investments to have any credit impairment. December 31, 2022 Less than 12 months 12 months or more Total Unrealized Fair Unrealized Fair Unrealized Fair (In thousands) Available-for-sale securities Corporate debt securities $ (24,421) $ 217,278 $ — $ — $ (24,421) $ 217,278 Municipal bonds (900) 14,704 — — (900) 14,704 U.S. government and agency securities $ (120) $ 28,002 $ (805) $ 7,604 $ (925) $ 35,606 Asset-backed securities (16,304) 593,310 (3,884) 72,112 (20,188) 665,422 Mortgage-backed securities (59,338) 833,728 (14,318) 77,584 (73,656) 911,312 (101,083) 1,687,022 (19,007) 157,300 (120,090) 1,844,322 Held-to-maturity securities Mortgage-backed securities (51,411) 400,422 — — (51,411) 400,422 $ (152,494) $ 2,087,444 $ (19,007) $ 157,300 $ (171,501) $ 2,244,744 September 30, 2022 Less than 12 months 12 months or more Total Unrealized Fair Unrealized Fair Unrealized Fair (In thousands) Available-for-sale securities Corporate debt securities $ (27,072) $ 288,753 $ — $ — $ (27,072) $ 288,753 Municipal bonds due (1,061) 14,561 — — (1,061) 14,561 U.S. government and agency securities (1,049) 39,354 — — (1,049) 39,354 Asset-backed securities $ (6,374) $ 601,248 $ (1,383) $ 50,070 $ (7,757) $ 651,318 Mortgage-backed securities (63,738) 833,683 (12,331) 53,533 (76,069) 887,216 (99,294) 1,777,599 (13,714) 103,603 (113,008) 1,881,202 Held-to-maturity securities Mortgage-backed securities (56,461) 405,166 — — (56,461) 405,166 $ (155,755) $ 2,182,765 $ (13,714) $ 103,603 $ (169,469) $ 2,286,368

Derivatives and Hedging Activ_2

Derivatives and Hedging Activities (Tables)	3 Months Ended
	Dec. 31, 2022
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Fair Value, Notional Amount and Balance Sheet Classification	The following tables present the fair value, notional amount and balance sheet classification of derivative assets and liabilities at December 31, 2022 and September 30, 2022. December 31, 2022 Derivative Assets Derivative Liabilities Interest rate contract purpose Balance Sheet Location Notional Fair Value Balance Sheet Location Notional Fair Value (In thousands) (In thousands) Client swap program hedges Other assets $ 583,782 $ 63,383 Other liabilities $ 583,782 $ 63,383 Commercial loan fair value hedges Other assets 39,661 2,447 Other liabilities — — Mortgage loan fair value hedges Other assets 470,000 33,986 Other liabilities — — Borrowings cash flow hedges Other assets 1,000,000 173,139 Other liabilities — — $ 2,093,443 $ 272,955 $ 583,782 $ 63,383 September 30, 2022 Derivative Assets Derivative Liabilities Interest rate contract purpose Balance Sheet Location Notional Fair Value Balance Sheet Location Notional Fair Value (In thousands) (In thousands) Client swap program hedges Other assets $ 588,676 $ 67,260 Other liabilities $ 588,676 $ 67,260 Commercial loan fair value hedges Other assets 42,209 2,517 Other liabilities — — Mortgage loan fair value hedges Other assets 470,000 36,765 Other liabilities — — Borrowings cash flow hedges Other assets 1,000,000 179,945 Other liabilities — — $ 2,100,885 $ 286,487 $ 588,676 $ 67,260
Schedule of Fair Value Hedge Accounting on Carrying Value of Hedged Items	The following tables present the impact of fair value hedge accounting on the carrying value of the hedged items at December 31, 2022 and September 30, 2022. (In thousands) December 31, 2022 Balance sheet line item in which hedged item is recorded Carrying value of hedged items Cumulative gain (loss) fair value hedge adjustment included in carrying amount of hedged items Loans receivable (1) (2) $ 1,131,282 $ (35,958) $ 1,131,282 $ (35,958) (1) Includes the amortized cost basis of the closed mortgage loan portfolios used to designate the hedging relationships in which the hedged items are the last layer expected to be remaining at the end of the hedging relationships. At December 31, 2022, the amortized cost basis of the closed loan portfolios used in the hedging relationships was $1,094,211,000, the cumulative basis adjustment associated with the hedging relationships was $(33,423,000), and the amount of the designated hedged items was $470,000,000. (2) Includes the amortized cost basis of commercial loans designated in fair value hedging relationships. At December 31, 2022, the amortized cost basis of the hedged commercial loans was $37,071,000 and the cumulative basis adjustment associated with the hedging relationships was $(2,535,000). (In thousands) September 30, 2022 Balance sheet line item in which hedged item is recorded Carrying value of hedged items Cumulative gain (loss) fair value hedge adjustment included in carrying amount of hedged items Loans receivable (1) (2) $ 1,159,496 $ (39,090) $ 1,159,496 $ (39,090) (1) Includes the amortized cost basis of the closed mortgage loan portfolios used to designate the hedging relationships in which the hedged items are the last layer expected to be remaining at the end of the hedging relationships. At September 30, 2022, the amortized cost basis of the closed loan portfolios used in the hedging relationships was $1,119,975,000, the cumulative basis adjustment associated with the hedging relationships was $(36,458,000), and the amount of the designated hedged items was $470,000,000.
Schedule of Impact of Derivative Instruments	The following table presents the impact of derivative instruments (cash flow hedges on borrowings) on AOCI for the periods presented. (In thousands) Three Months Ended December 31, Amount of gain/(loss) recognized in AOCI on derivatives in cash flow hedging relationships 2022 2021 Interest rate contracts: Pay fixed/receive floating swaps on borrowings cash flow hedges $ (6,806) $ 6,446 Total pre-tax gain/(loss) recognized in AOCI $ (6,806) $ 6,446 The following tables present the impact of derivative instruments (client swap program) that are not designated in accounting hedges under ASC 815 for the periods presented. (In thousands) Three Months Ended December 31, Derivative instruments Classification of gain/(loss) recognized in income on derivative instrument 2022 2021 Interest rate contracts: Pay fixed/receive floating swap Other noninterest income $ (3,878) $ 5,039 Receive fixed/pay floating swap Other noninterest income 3,878 (5,039) $ — $ —
Schedule of Derivatives Instruments Statements of Financial Performance and Financial Position, Location	The following tables present the gain (loss) on derivative instruments in fair value and cash flow accounting hedging relationships under ASC 815 for the periods presented. Three Months Ended December 31, 2022 Three Months Ended December 31, 2021 Interest income on loans receivable Interest expense on FHLB advances Interest income on loans receivable Interest expense on FHLB advances (In thousands) (In thousands) Interest income/(expense), including the effects of fair value and cash flow hedges $ 203,946 $ (18,974) $ 138,509 $ (7,843) Gain/(loss) on fair value hedging relationships: Interest rate contracts Amounts related to interest settlements on derivatives $ 3,167 $ (1,371) Recognized on derivatives (2,849) 4,500 Recognized on hedged items 3,132 (4,475) Net income/(expense) recognized on fair value hedges $ 3,450 $ (1,346) Gain/(loss) on cash flow hedging relationships: Interest rate contracts Amounts related to interest settlements on derivatives $ 7,274 $ 2,021 Amount of derivative gain/(loss) reclassified from AOCI into interest income/expense — — Net income/(expense) recognized on cash flow hedges $ 7,274 $ 2,021

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Details) $ / shares in Units, $ in Thousands		3 Months Ended
	Feb. 08, 2021 USD ($) $ / shares shares	Dec. 31, 2022 USD ($) branch classOfPortfolioSegment portfolioSegment	Sep. 30, 2022 USD ($)
Accounting Policies [Line Items]
Number of bank branches | branch		200
Dividend rate	4.875%
Proceeds from issuance of preferred stock, net	$ 293,325
Cash collateral		$ (280,400)	$ (284,400)
Fair value of NAV		38,385
Remaining unfunded commitment		$ 7,511
Number of portfolio segments for loans held for investment | portfolioSegment		2
Number of classes disaggregating the commercial loan portfolio | classOfPortfolioSegment		5
Number of classes disaggregating the consumer loan portfolio | classOfPortfolioSegment		5
Loans in process		$ 2,997,839	3,006,023
Financing Receivable
Accounting Policies [Line Items]
Loans in process		$ 4,822,769	$ 4,947,570
Public Offering
Accounting Policies [Line Items]
Number of depositary shares | shares	12,000,000
Percentage of preferred stock	2.50%
Public offering price (in usd per share) | $ / shares	$ 25
Series A Preferred Stock | Public Offering
Accounting Policies [Line Items]
Number of depositary shares | shares	300,000

Dividends and Share Repurchas_2

Dividends and Share Repurchases (Details) - $ / shares						3 Months Ended
	Dec. 02, 2022	Oct. 15, 2022	Jul. 15, 2022	Apr. 15, 2022	Jan. 15, 2022	Dec. 31, 2022	Dec. 31, 2021
Stockholders' Equity Note [Abstract]
Cash dividends per share (in dollars per share)	$ 0.24					$ 0.24	$ 0.23
Stock repurchased (in shares)						44,845
Average cost per share (in dollars per share)						$ 38.53
Remaining shares authorized to be repurchased (in shares)						3,679,499
Preferred stock dividends declared (in dollars per share)		$ 12.1875	$ 12.1875	$ 12.1875	$ 12.1875
Depository dividends declared (in dollars per share)		$ 0.30468750	$ 0.30468750	$ 0.30468750	$ 0.30468750

Loans Receivable - Schedule of

Loans Receivable - Schedule of Loans Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 20,260,711	$ 19,384,959
Ratio of loan type to all loans	100%	100%
Allowance for credit losses on loans	$ 176,797	$ 172,808	$ 171,411	$ 171,300
Loans in process	2,997,839	3,006,023
Net deferred fees, costs and discounts	92,487	92,564
Total loan contra accounts	3,267,123	3,271,395
Net loans	16,993,588	16,113,564
Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 12,887,691	$ 12,206,134
Ratio of loan type to all loans	63.60%	63%
Allowance for credit losses on loans	$ 138,282	$ 133,476	127,837	125,375
Commercial loans | Multi-family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 2,713,331	$ 2,645,801
Ratio of loan type to all loans	13.40%	13.70%
Allowance for credit losses on loans	$ 12,324	$ 12,013	15,993	16,949
Commercial loans | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 3,237,073	$ 3,133,660
Ratio of loan type to all loans	16%	16.20%
Allowance for credit losses on loans	$ 27,380	$ 25,814	25,722	23,437
Commercial loans | Commercial & industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 2,628,131	$ 2,350,984
Ratio of loan type to all loans	13%	12.10%
Allowance for credit losses on loans	$ 63,873	$ 57,210	47,231	45,957
Commercial loans | Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 4,055,474	$ 3,784,388
Ratio of loan type to all loans	20%	19.50%
Allowance for credit losses on loans	$ 26,133	$ 26,161	24,766	25,585
Commercial loans | Land - acquisition & development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 253,682	$ 291,301
Ratio of loan type to all loans	1.20%	1.50%
Allowance for credit losses on loans	$ 8,572	$ 12,278	14,125	13,447
Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 7,373,020	$ 7,178,825
Ratio of loan type to all loans	36.40%	37%
Allowance for credit losses on loans	$ 38,515	$ 39,332	43,574	45,925
Consumer loans | Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 926,126	$ 974,652
Ratio of loan type to all loans	4.60%	5%
Allowance for credit losses on loans	$ 3,500	$ 3,410	3,719	4,907
Consumer loans | Single-family residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 6,013,410	$ 5,771,862
Ratio of loan type to all loans	29.70%	29.80%
Allowance for credit losses on loans	$ 25,475	$ 25,518	30,106	30,978
Consumer loans | Land - consumer lot loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 148,246	$ 153,240
Ratio of loan type to all loans	0.70%	0.80%
Allowance for credit losses on loans	$ 4,142	$ 5,047	4,984	4,939
Consumer loans | HELOC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 212,123	$ 203,528
Ratio of loan type to all loans	1%	1%
Allowance for credit losses on loans	$ 2,588	$ 2,482	2,365	2,390
Consumer loans | Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 73,115	$ 75,543
Ratio of loan type to all loans	0.40%	0.40%
Allowance for credit losses on loans	$ 2,810	$ 2,875	$ 2,400	$ 2,711

Loans Receivable - Narrative (D

Loans Receivable - Narrative (Details) $ in Thousands	3 Months Ended
	Dec. 31, 2022 USD ($) portfolioSegment	Sep. 30, 2022 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of portfolio segments for loans held for investment | portfolioSegment	2
Accrued interest receivables for loans	$ 67,169	$ 57,070
Loans pledged to secure borrowings from the Federal Home Loan Bank	8,636,895	$ 8,224,951
Nonaccrual interest income recognized	534
Impaired, interest income on accrual accrual and performed loans	$ 358
Basis point reduction, minimum	1%
Basis point reduction, maximum	2%
Percent of TDRs classified as performing	98%
Single family residential loans as percentage of restructured loans	82.50%
Performing Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructuring, amount	$ 55,515
Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Term for payment and rate reduction	6 months
Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Term for payment and rate reduction	24 months

Loans Receivable - Non-accrual

Loans Receivable - Non-accrual Loans and Loans 90 Days or More Past Due and Accruing (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual percent of total loans	0.17%	0.21%
Financial Asset Originated
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	$ 29,180	$ 34,534
Non-accrual with no ACL	906	1,308
90 days or more past due and accruing	0	0
Financial Asset Originated | Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	11,420	16,296
Non-accrual with no ACL	906	1,308
90 days or more past due and accruing	0	0
Financial Asset Originated | Commercial loans | Multi-family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	5,879	5,912
Non-accrual with no ACL	0	0
90 days or more past due and accruing	0	0
Financial Asset Originated | Commercial loans | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	4,635	4,691
Non-accrual with no ACL	0	0
90 days or more past due and accruing	0	0
Financial Asset Originated | Commercial loans | Commercial & industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	906	5,693
Non-accrual with no ACL	906	1,308
90 days or more past due and accruing	0	0
Financial Asset Originated | Commercial loans | Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	0	0
Non-accrual with no ACL	0	0
90 days or more past due and accruing	0	0
Financial Asset Originated | Commercial loans | Land - acquisition & development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	0	0
Non-accrual with no ACL	0	0
90 days or more past due and accruing	0	0
Financial Asset Originated | Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	17,760	18,238
Non-accrual with no ACL	0	0
90 days or more past due and accruing	0	0
Financial Asset Originated | Consumer loans | Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	435	435
Non-accrual with no ACL	0	0
90 days or more past due and accruing	0	0
Financial Asset Originated | Consumer loans | Single-family residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	17,084	17,450
Non-accrual with no ACL	0	0
90 days or more past due and accruing	0	0
Financial Asset Originated | Consumer loans | Land - consumer lot loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	71	84
Non-accrual with no ACL	0	0
90 days or more past due and accruing	0	0
Financial Asset Originated | Consumer loans | HELOC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	134	233
Non-accrual with no ACL	0	0
90 days or more past due and accruing	0	0
Financial Asset Originated | Consumer loans | Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	36	36
Non-accrual with no ACL	0	0
90 days or more past due and accruing	$ 0	$ 0

Loans Receivable - Loan Delinqu

Loans Receivable - Loan Delinquencies by Loan Portfolio and Class (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 17,170,385	$ 16,286,372
% based on $, past due	0.16%	0.17%
Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 17,142,676	$ 16,259,445
% based on $, current	99.84%	99.83%
Financial Asset, Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 27,709	$ 26,927
% based on $, past due	0.16%	0.17%
30 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 9,613	$ 3,651
% based on $, past due	0.06%	0.02%
60 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 2,745	$ 2,887
% based on $, past due	0.01%	0.02%
90 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 15,351	$ 20,389
% based on $, past due	0.09%	0.13%
Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 10,358,994	$ 9,728,501
% based on $, past due	0.03%	0.08%
Commercial loans | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 10,355,765	$ 9,720,833
Commercial loans | Financial Asset, Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	3,229	7,668
Commercial loans | 30 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	1,728	538
Commercial loans | 60 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	533	1,369
Commercial loans | 90 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	968	5,761
Commercial loans | Multi-family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 2,695,759	$ 2,626,479
% based on $, past due	0%	0%
Commercial loans | Multi-family | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 2,695,759	$ 2,626,479
Commercial loans | Multi-family | Financial Asset, Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	0	0
Commercial loans | Multi-family | 30 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	0	0
Commercial loans | Multi-family | 60 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	0	0
Commercial loans | Multi-family | 90 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	0	0
Commercial loans | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 3,213,308	$ 3,111,112
% based on $, past due	0.03%	0.03%
Commercial loans | Commercial real estate | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 3,212,259	$ 3,110,056
Commercial loans | Commercial real estate | Financial Asset, Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	1,049	1,056
Commercial loans | Commercial real estate | 30 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	533	538
Commercial loans | Commercial real estate | 60 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	452	450
Commercial loans | Commercial real estate | 90 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	64	68
Commercial loans | Commercial & industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 2,621,266	$ 2,343,403
% based on $, past due	0.05%	0.28%
Commercial loans | Commercial & industrial | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 2,620,020	$ 2,336,791
Commercial loans | Commercial & industrial | Financial Asset, Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	1,246	6,612
Commercial loans | Commercial & industrial | 30 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	261	0
Commercial loans | Commercial & industrial | 60 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	81	919
Commercial loans | Commercial & industrial | 90 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	904	5,693
Commercial loans | Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 1,637,499	$ 1,423,891
% based on $, past due	0.06%	0%
Commercial loans | Construction | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 1,636,565	$ 1,423,891
Commercial loans | Construction | Financial Asset, Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	934	0
Commercial loans | Construction | 30 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	934	0
Commercial loans | Construction | 60 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	0	0
Commercial loans | Construction | 90 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable
Commercial loans | Land - acquisition & development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 191,162	$ 223,616
% based on $, past due	0%	0%
Commercial loans | Land - acquisition & development | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 191,162	$ 223,616
Commercial loans | Land - acquisition & development | Financial Asset, Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	0	0
Commercial loans | Land - acquisition & development | 30 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	0	0
Commercial loans | Land - acquisition & development | 60 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	0	0
Commercial loans | Land - acquisition & development | 90 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	0	0
Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 6,811,391	$ 6,557,871
% based on $, past due	0.36%	0.29%
Consumer loans | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 6,786,911	$ 6,538,612
Consumer loans | Financial Asset, Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	24,480	19,259
Consumer loans | 30 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	7,885	3,113
Consumer loans | 60 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	2,212	1,518
Consumer loans | 90 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	14,383	14,628
Consumer loans | Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 408,563	$ 397,343
% based on $, past due	0.11%	0.11%
Consumer loans | Construction | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 408,128	$ 396,908
Consumer loans | Construction | Financial Asset, Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	435	435
Consumer loans | Construction | 30 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	0	0
Consumer loans | Construction | 60 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	0	0
Consumer loans | Construction | 90 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	435	435
Consumer loans | Single-family residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 5,967,678	$ 5,726,979
% based on $, past due	0.36%	0.31%
Consumer loans | Single-family residential | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 5,946,382	$ 5,708,996
Consumer loans | Single-family residential | Financial Asset, Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	21,296	17,983
Consumer loans | Single-family residential | 30 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	5,661	2,796
Consumer loans | Single-family residential | 60 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	2,038	1,316
Consumer loans | Single-family residential | 90 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	13,597	13,871
Consumer loans | Land - consumer lot loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 147,078	$ 151,945
% based on $, past due	0.07%	0.13%
Consumer loans | Land - consumer lot loans | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 146,969	$ 151,746
Consumer loans | Land - consumer lot loans | Financial Asset, Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	109	199
Consumer loans | Land - consumer lot loans | 30 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	49	0
Consumer loans | Land - consumer lot loans | 60 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	0	139
Consumer loans | Land - consumer lot loans | 90 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	60	60
Consumer loans | HELOC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 214,904	$ 206,033
% based on $, past due	1.05%	0.21%
Consumer loans | HELOC | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 212,655	$ 205,605
Consumer loans | HELOC | Financial Asset, Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	2,249	428
Consumer loans | HELOC | 30 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	2,121	155
Consumer loans | HELOC | 60 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	0	46
Consumer loans | HELOC | 90 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	128	227
Consumer loans | Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 73,168	$ 75,571
% based on $, past due	0.53%	0.28%
Consumer loans | Consumer | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 72,777	$ 75,357
Consumer loans | Consumer | Financial Asset, Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	391	214
Consumer loans | Consumer | 30 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	54	162
Consumer loans | Consumer | 60 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	174	17
Consumer loans | Consumer | 90 Days Delinquent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 163	$ 35

Loans Receivable - Loans Based

Loans Receivable - Loans Based on Credit Quality Indicators (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022
Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023		$ 0
2022		1,594
2021		0
2020		0
2019		0
Prior to 2019		0
Revolving Loans		0
Revolving to Term Loans		0
Total Loans		1,594
Commercial loans
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	$ 372,249	2,351,822
2022	2,509,270	2,646,527
2021	2,593,210	1,316,898
2020	1,297,514	574,962
2019	571,392	422,204
Prior to 2019	1,456,736	1,120,742
Revolving Loans	1,556,712	1,295,091
Revolving to Term Loans	1,911	255
Total Loans	10,358,994	9,728,501
Commercial loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	372,249	2,343,088
2022	2,485,829	2,630,037
2021	2,573,937	1,299,292
2020	1,261,433	539,354
2019	534,822	409,574
Prior to 2019	1,407,932	1,082,730
Revolving Loans	1,467,037	1,204,597
Revolving to Term Loans	1,911	255
Total Loans	10,105,150	9,508,927
Commercial loans | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	2,503
2022	0	1,594
2021	2,601	0
2020	0	0
2019	1,382	0
Prior to 2019	0	0
Revolving Loans	2,850	29,153
Revolving to Term Loans	0	0
Total Loans	6,833	33,250
Commercial loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	6,231
2022	23,441	14,896
2021	16,672	17,606
2020	36,081	35,608
2019	35,188	12,630
Prior to 2019	48,804	38,012
Revolving Loans	86,825	61,341
Revolving to Term Loans	0	0
Total Loans	247,011	186,324
Commercial loans | Multi-family
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	94,649	661,095
2022	670,726	778,936
2021	763,102	502,646
2020	490,648	168,568
2019	167,495	163,704
Prior to 2019	472,778	317,428
Revolving Loans	36,361	34,102
Revolving to Term Loans	0	0
Total Loans	2,695,759	2,626,479
Commercial loans | Multi-family | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	94,649	657,144
2022	666,795	778,936
2021	763,102	500,917
2020	486,468	168,568
2019	167,495	157,144
Prior to 2019	464,692	315,858
Revolving Loans	36,361	34,102
Revolving to Term Loans	0	0
Total Loans	2,679,562	2,612,669
Commercial loans | Multi-family | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	3,951
2022	3,931	0
2021	0	1,729
2020	4,180	0
2019	0	6,560
Prior to 2019	8,086	1,570
Revolving Loans	0	0
Revolving to Term Loans	0	0
Total Loans	16,197	13,810
Commercial loans | Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	130,440	820,749
2022	812,040	680,915
2021	723,882	498,900
2020	494,025	331,612
2019	328,075	223,028
Prior to 2019	720,901	551,931
Revolving Loans	3,945	3,977
Revolving to Term Loans	0	0
Total Loans	3,213,308	3,111,112
Commercial loans | Commercial real estate | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	130,440	820,490
2022	806,478	679,321
2021	722,298	492,826
2020	467,416	301,033
2019	296,176	218,171
Prior to 2019	705,610	541,008
Revolving Loans	1,375	1,391
Revolving to Term Loans	0	0
Total Loans	3,129,793	3,054,240
Commercial loans | Commercial real estate | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0
2022	0
2021	0
2020	0
2019	1,382
Prior to 2019	0
Revolving Loans	0
Revolving to Term Loans	0
Total Loans	1,382
Commercial loans | Commercial real estate | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	259
2022	5,562	0
2021	1,584	6,074
2020	26,609	30,579
2019	30,517	4,857
Prior to 2019	15,291	10,923
Revolving Loans	2,570	2,586
Revolving to Term Loans	0	0
Total Loans	82,133	55,278
Commercial loans | Commercial & industrial
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	124,523	259,192
2022	280,121	448,269
2021	360,596	155,602
2020	140,225	44,131
2019	39,256	26,922
Prior to 2019	236,750	223,428
Revolving Loans	1,437,884	1,185,604
Revolving to Term Loans	1,911	255
Total Loans	2,621,266	2,343,403
Commercial loans | Commercial & industrial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	124,523	254,668
2022	272,160	435,630
2021	345,166	145,799
2020	134,933	39,102
2019	34,585	25,709
Prior to 2019	211,323	197,909
Revolving Loans	1,350,779	1,097,696
Revolving to Term Loans	1,911	255
Total Loans	2,475,380	2,196,768
Commercial loans | Commercial & industrial | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	2,503
2022	0	0
2021	2,601	0
2020	0	0
2019	0	0
Prior to 2019	0	0
Revolving Loans	2,850	29,153
Revolving to Term Loans	0	0
Total Loans	5,451	31,656
Commercial loans | Commercial & industrial | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	2,021
2022	7,961	12,639
2021	12,829	9,803
2020	5,292	5,029
2019	4,671	1,213
Prior to 2019	25,427	25,519
Revolving Loans	84,255	58,755
Revolving to Term Loans	0	0
Total Loans	140,435	114,979
Commercial loans | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	17,955	510,764
2022	657,795	673,868
2021	696,773	142,816
2020	155,086	27,260
2019	33,585	375
Prior to 2019	375	0
Revolving Loans	75,930	68,808
Revolving to Term Loans	0	0
Total Loans	1,637,499	1,423,891
Commercial loans | Construction | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	17,955	510,764
2022	651,808	671,611
2021	694,514	142,816
2020	155,086	27,260
2019	33,585	375
Prior to 2019	375	0
Revolving Loans	75,930	68,808
Revolving to Term Loans	0	0
Total Loans	1,629,253	1,421,634
Commercial loans | Construction | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	0
2022	5,987	2,257
2021	2,259	0
2020	0	0
2019	0	0
Prior to 2019	0	0
Revolving Loans	0	0
Revolving to Term Loans	0	0
Total Loans	8,246	2,257
Commercial loans | Land - acquisition & development
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	4,682	100,022
2022	88,588	64,539
2021	48,857	16,934
2020	17,530	3,391
2019	2,981	8,175
Prior to 2019	25,932	27,955
Revolving Loans	2,592	2,600
Revolving to Term Loans	0	0
Total Loans	191,162	223,616
Commercial loans | Land - acquisition & development | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	4,682	100,022
2022	88,588	64,539
2021	48,857	16,934
2020	17,530	3,391
2019	2,981	8,175
Prior to 2019	25,932	27,955
Revolving Loans	2,592	2,600
Revolving to Term Loans	0	0
Total Loans	191,162	223,616
Consumer loans
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	224,142	1,420,965
2022	1,520,989	1,873,721
2021	1,867,755	806,033
2020	796,591	328,430
2019	320,649	303,923
Prior to 2019	1,847,441	1,598,038
Revolving Loans	233,299	225,772
Revolving to Term Loans	525	989
Total Loans	6,811,391	6,557,871
Consumer loans | Current
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	224,142	1,420,964
2022	1,520,987	1,873,286
2021	1,865,683	805,494
2020	796,591	327,315
2019	319,469	303,923
Prior to 2019	1,828,221	1,581,180
Revolving Loans	231,293	225,461
Revolving to Term Loans	525	989
Total Loans	6,786,911	6,538,612
Consumer loans | 30 days past due
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	0
2022	0	0
2021	1,637	400
2020	0	606
2019	63	0
Prior to 2019	4,307	2,040
Revolving Loans	1,878	67
Revolving to Term Loans	0	0
Total Loans	7,885	3,113
Consumer loans | 60 days past due
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	0
2022	0	0
2021	0	139
2020	0	0
2019	1	0
Prior to 2019	2,211	1,362
Revolving Loans	0	17
Revolving to Term Loans	0	0
Total Loans	2,212	1,518
Consumer loans | 90+ days past due
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	1
2022	2	435
2021	435	0
2020	0	509
2019	1,116	0
Prior to 2019	12,702	13,456
Revolving Loans	128	227
Revolving to Term Loans	0	0
Total Loans	14,383	14,628
Consumer loans | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	235,030
2022	320,079	150,869
2021	82,784	9,811
2020	4,864	1,155
2019	358	478
Prior to 2019	478	0
Revolving Loans	0	0
Revolving to Term Loans	0	0
Total Loans	408,563	397,343
Consumer loans | Construction | Current
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	235,030
2022	320,079	150,434
2021	82,349	9,811
2020	4,864	1,155
2019	358	478
Prior to 2019	478	0
Revolving Loans	0	0
Revolving to Term Loans	0	0
Total Loans	408,128	396,908
Consumer loans | Construction | 90+ days past due
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	0
2022	0	435
2021	435	0
2020	0	0
2019	0	0
Prior to 2019	0	0
Revolving Loans	0	0
Revolving to Term Loans	0	0
Total Loans	435	435
Consumer loans | Single-family residential
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	219,679	1,131,152
2022	1,148,027	1,652,242
2021	1,719,327	772,169
2020	768,368	321,627
2019	314,866	276,093
Prior to 2019	1,797,411	1,573,696
Revolving Loans	0	0
Revolving to Term Loans	0	0
Total Loans	5,967,678	5,726,979
Consumer loans | Single-family residential | Current
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	219,679	1,131,152
2022	1,148,027	1,652,242
2021	1,717,690	771,769
2020	768,368	320,546
2019	313,719	276,093
Prior to 2019	1,778,899	1,557,194
Revolving Loans	0	0
Revolving to Term Loans	0	0
Total Loans	5,946,382	5,708,996
Consumer loans | Single-family residential | 30 days past due
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	0
2022	0	0
2021	1,637	400
2020	0	604
2019	63	0
Prior to 2019	3,961	1,792
Revolving Loans	0	0
Revolving to Term Loans	0	0
Total Loans	5,661	2,796
Consumer loans | Single-family residential | 60 days past due
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	0
2022	0	0
2021	0	0
2020	0	0
2019	0	0
Prior to 2019	2,038	1,316
Revolving Loans	0	0
Revolving to Term Loans	0	0
Total Loans	2,038	1,316
Consumer loans | Single-family residential | 90+ days past due
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	0
2022	0	0
2021	0	0
2020	0	477
2019	1,084	0
Prior to 2019	12,513	13,394
Revolving Loans	0	0
Revolving to Term Loans	0	0
Total Loans	13,597	13,871
Consumer loans | Land - consumer lot loans
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	4,355	53,396
2022	50,736	60,454
2021	55,658	16,015
2020	15,336	5,399
2019	5,189	3,433
Prior to 2019	15,804	13,248
Revolving Loans	0	0
Revolving to Term Loans	0	0
Total Loans	147,078	151,945
Consumer loans | Land - consumer lot loans | Current
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	4,355	53,396
2022	50,736	60,454
2021	55,658	15,876
2020	15,336	5,399
2019	5,189	3,433
Prior to 2019	15,695	13,188
Revolving Loans	0	0
Revolving to Term Loans	0	0
Total Loans	146,969	151,746
Consumer loans | Land - consumer lot loans | 30 days past due
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	0
2022	0	0
2021	0	139
2020	0	0
2019	0	0
Prior to 2019	49	0
Revolving Loans	0	0
Revolving to Term Loans	0	0
Total Loans	49	139
Consumer loans | Land - consumer lot loans | 90+ days past due
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	0
2022	0	0
2021	0	0
2020	0	0
2019	0	0
Prior to 2019	60	60
Revolving Loans	0	0
Revolving to Term Loans	0	0
Total Loans	60	60
Consumer loans | HELOC
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	0
2022	0	0
2021	0	0
2020	0	0
2019	0	0
Prior to 2019	5,106	4,473
Revolving Loans	209,273	200,571
Revolving to Term Loans	525	989
Total Loans	214,904	206,033
Consumer loans | HELOC | Current
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	0
2022	0	0
2021	0	0
2020	0	0
2019	0	0
Prior to 2019	4,846	4,349
Revolving Loans	207,284	200,267
Revolving to Term Loans	525	989
Total Loans	212,655	205,605
Consumer loans | HELOC | 30 days past due
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	0
2022	0	0
2021	0	0
2020	0	0
2019	0	0
Prior to 2019	260	95
Revolving Loans	1,861	60
Revolving to Term Loans	0	0
Total Loans	2,121	155
Consumer loans | HELOC | 60 days past due
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023		0
2022		0
2021		0
2020		0
2019		0
Prior to 2019		29
Revolving Loans		17
Revolving to Term Loans		0
Total Loans		46
Consumer loans | HELOC | 90+ days past due
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	0
2022	0	0
2021	0	0
2020	0	0
2019	0	0
Prior to 2019	0	0
Revolving Loans	128	227
Revolving to Term Loans	0	0
Total Loans	128	227
Consumer loans | Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	108	1,387
2022	2,147	10,156
2021	9,986	8,038
2020	8,023	249
2019	236	23,919
Prior to 2019	28,642	6,621
Revolving Loans	24,026	25,201
Revolving to Term Loans	0	0
Total Loans	73,168	75,571
Consumer loans | Consumer | Current
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	108	1,386
2022	2,145	10,156
2021	9,986	8,038
2020	8,023	215
2019	203	23,919
Prior to 2019	28,303	6,449
Revolving Loans	24,009	25,194
Revolving to Term Loans	0	0
Total Loans	72,777	75,357
Consumer loans | Consumer | 30 days past due
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	0
2022	0	0
2021	0	0
2020	0	2
2019	0	0
Prior to 2019	37	153
Revolving Loans	17	7
Revolving to Term Loans	0	0
Total Loans	54	162
Consumer loans | Consumer | 60 days past due
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	0
2022	0	0
2021	0	0
2020	0	0
2019	1	0
Prior to 2019	173	17
Revolving Loans	0	0
Revolving to Term Loans	0	0
Total Loans	174	17
Consumer loans | Consumer | 90+ days past due
Financing Receivable, Credit Quality Indicator [Line Items]
YTD 2023	0	1
2022	2	0
2021	0	0
2020	0	32
2019	32	0
Prior to 2019	129	2
Revolving Loans	0	0
Revolving to Term Loans	0	0
Total Loans	$ 163	$ 35

Allowance for Loan Losses - All

Allowance for Loan Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Allowance	$ 172,808	$ 171,300
Charge-offs	(228)	(677)
Recoveries	717	2,788
Provision & Transfers	3,500	(2,000)
Ending Allowance	176,797	171,411
Unfunded commitments
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Provision & Transfers	(1,000)	2,500
Commercial loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Allowance	133,476	125,375
Charge-offs	(82)	(574)
Recoveries	52	2,126
Provision & Transfers	4,836	910
Ending Allowance	138,282	127,837
Commercial loans | Multi-family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Allowance	12,013	16,949
Charge-offs	0	0
Recoveries	0	0
Provision & Transfers	311	(956)
Ending Allowance	12,324	15,993
Commercial loans | Commercial real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Allowance	25,814	23,437
Charge-offs	0	(529)
Recoveries	4	44
Provision & Transfers	1,562	2,770
Ending Allowance	27,380	25,722
Commercial loans | Commercial & industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Allowance	57,210	45,957
Charge-offs	(82)	(43)
Recoveries	32	62
Provision & Transfers	6,713	1,255
Ending Allowance	63,873	47,231
Commercial loans | Construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Allowance	26,161	25,585
Charge-offs	0	0
Recoveries	0	2,000
Provision & Transfers	(28)	(2,819)
Ending Allowance	26,133	24,766
Commercial loans | Land - acquisition & development
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Allowance	12,278	13,447
Charge-offs	0	(2)
Recoveries	16	20
Provision & Transfers	(3,722)	660
Ending Allowance	8,572	14,125
Consumer loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Allowance	39,332	45,925
Charge-offs	(146)	(103)
Recoveries	665	662
Provision & Transfers	(1,336)	(2,910)
Ending Allowance	38,515	43,574
Consumer loans | Construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Allowance	3,410	4,907
Charge-offs	0	0
Recoveries	0	0
Provision & Transfers	90	(1,188)
Ending Allowance	3,500	3,719
Consumer loans | Single-family residential
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Allowance	25,518	30,978
Charge-offs	0	0
Recoveries	430	405
Provision & Transfers	(473)	(1,277)
Ending Allowance	25,475	30,106
Consumer loans | Land - consumer lot loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Allowance	5,047	4,939
Charge-offs	0	(27)
Recoveries	0	5
Provision & Transfers	(905)	67
Ending Allowance	4,142	4,984
Consumer loans | HELOC
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Allowance	2,482	2,390
Charge-offs	0	0
Recoveries	1	1
Provision & Transfers	105	(26)
Ending Allowance	2,588	2,365
Consumer loans | Consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Allowance	2,875	2,711
Charge-offs	(146)	(76)
Recoveries	234	251
Provision & Transfers	(153)	(486)
Ending Allowance	$ 2,810	$ 2,400

Allowance for Loan Losses - Nar

Allowance for Loan Losses - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Sep. 30, 2022	Sep. 30, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Provision for credit losses	$ 2,500	$ 500
Recoveries, net of charge-offs	489	2,111
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	176,797	171,411	$ 172,808	$ 171,300
Net loans	16,993,588		16,113,564
Gross loans	$ 17,170,385		$ 16,286,372
% based on $, past due	0.16%		0.17%
Financial Asset Originated
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	$ 29,180		$ 34,534
Non-Performing Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 38,650		$ 44,554
Ratio of non-performing assets to total assets	0.18%		0.21%
Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	$ 138,282	127,837	$ 133,476	125,375
Gross loans	$ 10,358,994		$ 9,728,501
% based on $, past due	0.03%		0.08%
Commercial loans | Financial Asset Originated
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	$ 11,420		$ 16,296
Commercial loans | Commercial & industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	63,873	$ 47,231	57,210	$ 45,957
Gross loans	$ 2,621,266		$ 2,343,403
% based on $, past due	0.05%		0.28%
Commercial loans | Commercial & industrial | Financial Asset Originated
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	$ 906		$ 5,693

Allowance for Losses on Loans -

Allowance for Losses on Loans - Internally Assigned Grade (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Dec. 31, 2022	Mar. 31, 2022	Sep. 30, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	$ 17,170,385		$ 16,286,372
Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	$ 16,895,511		16,045,127
Pass | Accounts Receivable | Credit Concentration Risk
Financing Receivable, Credit Quality Indicator [Line Items]
Total grade as a % of total loans	98.40%	98.52%
Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	$ 6,833		33,250
Special mention | Accounts Receivable | Credit Concentration Risk
Financing Receivable, Credit Quality Indicator [Line Items]
Total grade as a % of total loans	0.04%	0.20%
Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	$ 268,041		207,995
Substandard | Accounts Receivable | Credit Concentration Risk
Financing Receivable, Credit Quality Indicator [Line Items]
Total grade as a % of total loans	1.56%	1.28%
Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	$ 0		0
Doubtful | Accounts Receivable | Credit Concentration Risk
Financing Receivable, Credit Quality Indicator [Line Items]
Total grade as a % of total loans	0%	0%
Loss
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	$ 0		0
Loss | Accounts Receivable | Credit Concentration Risk
Financing Receivable, Credit Quality Indicator [Line Items]
Total grade as a % of total loans	0%	0%
Commercial loans
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	$ 10,358,994		9,728,501
Commercial loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	10,105,150		9,508,927
Commercial loans | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	6,833		33,250
Commercial loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	247,011		186,324
Commercial loans | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Commercial loans | Loss
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Commercial loans | Multi-family
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	2,695,759		2,626,479
Commercial loans | Multi-family | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	2,679,562		2,612,669
Commercial loans | Multi-family | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Commercial loans | Multi-family | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	16,197		13,810
Commercial loans | Multi-family | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Commercial loans | Multi-family | Loss
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Commercial loans | Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	3,213,308		3,111,112
Commercial loans | Commercial real estate | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	3,129,793		3,054,241
Commercial loans | Commercial real estate | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	1,382		1,594
Commercial loans | Commercial real estate | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	82,133		55,277
Commercial loans | Commercial real estate | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Commercial loans | Commercial real estate | Loss
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Commercial loans | Commercial & industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	2,621,266		2,343,403
Commercial loans | Commercial & industrial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	2,475,380		2,196,767
Commercial loans | Commercial & industrial | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	5,451		31,656
Commercial loans | Commercial & industrial | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	140,435		114,980
Commercial loans | Commercial & industrial | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Commercial loans | Commercial & industrial | Loss
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Commercial loans | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	1,637,499		1,423,891
Commercial loans | Construction | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	1,629,253		1,421,634
Commercial loans | Construction | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Commercial loans | Construction | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	8,246		2,257
Commercial loans | Construction | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Commercial loans | Construction | Loss
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Commercial loans | Land - acquisition & development
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	191,162		223,616
Commercial loans | Land - acquisition & development | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	191,162		223,616
Commercial loans | Land - acquisition & development | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Commercial loans | Land - acquisition & development | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Commercial loans | Land - acquisition & development | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Commercial loans | Land - acquisition & development | Loss
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Consumer loans
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	6,811,391		6,557,871
Consumer loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	6,790,361		6,536,200
Consumer loans | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Consumer loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	21,030		21,671
Consumer loans | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Consumer loans | Loss
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Consumer loans | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	408,563		397,343
Consumer loans | Construction | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	408,127		396,908
Consumer loans | Construction | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Consumer loans | Construction | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	436		435
Consumer loans | Construction | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Consumer loans | Construction | Loss
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Consumer loans | Single-family residential
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	5,967,678		5,726,979
Consumer loans | Single-family residential | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	5,947,295		5,706,199
Consumer loans | Single-family residential | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Consumer loans | Single-family residential | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	20,383		20,780
Consumer loans | Single-family residential | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Consumer loans | Single-family residential | Loss
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Consumer loans | Land - consumer lot loans
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	147,078		151,945
Consumer loans | Land - consumer lot loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	147,007		151,723
Consumer loans | Land - consumer lot loans | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Consumer loans | Land - consumer lot loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	71		222
Consumer loans | Land - consumer lot loans | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Consumer loans | Land - consumer lot loans | Loss
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Consumer loans | HELOC
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	214,904		206,033
Consumer loans | HELOC | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	214,771		205,800
Consumer loans | HELOC | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Consumer loans | HELOC | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	133		233
Consumer loans | HELOC | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Consumer loans | HELOC | Loss
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Consumer loans | Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	73,168		75,571
Consumer loans | Consumer | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	73,161		75,570
Consumer loans | Consumer | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Consumer loans | Consumer | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	7		1
Consumer loans | Consumer | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	0		0
Consumer loans | Consumer | Loss
Financing Receivable, Credit Quality Indicator [Line Items]
Gross loans	$ 0		$ 0

Allowance for Losses on Loans_2

Allowance for Losses on Loans - Credit Risk Profile Based on Payment Activity (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 17,170,385	$ 16,286,372
Commercial loans
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	10,358,994	9,728,501
Commercial loans | Multi-family
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	2,695,759	2,626,479
Commercial loans | Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	3,213,308	3,111,112
Commercial loans | Commercial & industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	2,621,266	2,343,403
Commercial loans | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	1,637,499	1,423,891
Commercial loans | Land - acquisition & development
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	191,162	223,616
Consumer loans
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	6,811,391	6,557,871
Consumer loans | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	408,563	397,343
Consumer loans | Single-family residential
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	5,967,678	5,726,979
Consumer loans | Land - consumer lot loans
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	147,078	151,945
Consumer loans | HELOC
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	214,904	206,033
Consumer loans | Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	73,168	75,571
Performing Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 17,141,205	$ 16,251,838
% of Total Loans	99.80%	99.80%
Performing Loans | Commercial loans
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 10,347,574	$ 9,712,205
% of Total Loans	99.90%	99.80%
Performing Loans | Commercial loans | Multi-family
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 2,689,880	$ 2,620,567
% of Total Loans	99.80%	99.80%
Performing Loans | Commercial loans | Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 3,208,673	$ 3,106,421
% of Total Loans	99.90%	99.80%
Performing Loans | Commercial loans | Commercial & industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 2,620,360	$ 2,337,710
% of Total Loans	100%	99.80%
Performing Loans | Commercial loans | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 1,637,499	$ 1,423,891
% of Total Loans	100%	100%
Performing Loans | Commercial loans | Land - acquisition & development
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 191,162	$ 223,616
% of Total Loans	100%	100%
Performing Loans | Consumer loans
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 6,793,631	$ 6,539,633
% of Total Loans	99.70%	99.70%
Performing Loans | Consumer loans | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 408,128	$ 396,908
% of Total Loans	99.90%	99.90%
Performing Loans | Consumer loans | Single-family residential
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 5,950,594	$ 5,709,529
% of Total Loans	99.70%	99.70%
Performing Loans | Consumer loans | Land - consumer lot loans
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 147,007	$ 151,861
% of Total Loans	100%	99.90%
Performing Loans | Consumer loans | HELOC
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 214,770	$ 205,800
% of Total Loans	99.90%	99.90%
Performing Loans | Consumer loans | Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 73,132	$ 75,535
% of Total Loans	100%	100%
Non-Performing Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 29,180	$ 34,534
% of Total Loans	0.20%	0.20%
Non-Performing Loans | Commercial loans
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 11,420	$ 16,296
% of Total Loans	0.10%	0.20%
Non-Performing Loans | Commercial loans | Multi-family
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 5,879	$ 5,912
% of Total Loans	0.20%	0.20%
Non-Performing Loans | Commercial loans | Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 4,635	$ 4,691
% of Total Loans	0.10%	0.20%
Non-Performing Loans | Commercial loans | Commercial & industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 906	$ 5,693
% of Total Loans	0%	0.20%
Non-Performing Loans | Commercial loans | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 0	$ 0
% of Total Loans	0%	0%
Non-Performing Loans | Commercial loans | Land - acquisition & development
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 0	$ 0
% of Total Loans	0%	0%
Non-Performing Loans | Consumer loans
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 17,760	$ 18,238
% of Total Loans	0.30%	0.40%
Non-Performing Loans | Consumer loans | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 435	$ 435
% of Total Loans	0.10%	0.10%
Non-Performing Loans | Consumer loans | Single-family residential
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 17,084	$ 17,450
% of Total Loans	0.30%	0.30%
Non-Performing Loans | Consumer loans | Land - consumer lot loans
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 71	$ 84
% of Total Loans	0%	0.10%
Non-Performing Loans | Consumer loans | HELOC
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 134	$ 233
% of Total Loans	0.10%	0.10%
Non-Performing Loans | Consumer loans | Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Amount	$ 36	$ 36
% of Total Loans	0%	0%

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	$ 2,059,837	$ 2,051,037
Total financial assets	2,461,892	2,457,897
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	2,059,837	2,051,037
Total financial assets	2,332,791	2,337,524
Total financial liabilities	63,383	67,260
Recurring | Client swap program hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	63,383	67,260
Derivative liabilities	63,383	67,260
Recurring | Commercial loan fair value hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	2,446	2,517
Recurring | Mortgage loan fair value hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	33,986	36,765
Recurring | Borrowings cash flow hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	173,139	179,945
Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	0	0
Total financial assets	0	0
Total financial liabilities	0	0
Recurring | Level 1 | Client swap program hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0	0
Derivative liabilities	0	0
Recurring | Level 1 | Commercial loan fair value hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0	0
Recurring | Level 1 | Mortgage loan fair value hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0	0
Recurring | Level 1 | Borrowings cash flow hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0	0
Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	2,059,837	2,051,037
Total financial assets	2,332,791	2,337,524
Total financial liabilities	63,383	67,260
Recurring | Level 2 | Client swap program hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	63,383	67,260
Derivative liabilities	63,383	67,260
Recurring | Level 2 | Commercial loan fair value hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	2,446	2,517
Recurring | Level 2 | Mortgage loan fair value hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	33,986	36,765
Recurring | Level 2 | Borrowings cash flow hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	173,139	179,945
Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	0	0
Total financial assets	0	0
Total financial liabilities	0	0
Recurring | Level 3 | Client swap program hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0	0
Derivative liabilities	0	0
Recurring | Level 3 | Commercial loan fair value hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0	0
Recurring | Level 3 | Mortgage loan fair value hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0	0
Recurring | Level 3 | Borrowings cash flow hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0	0
U.S. government and agency securities | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	99,889	39,354
U.S. government and agency securities | Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	0	0
U.S. government and agency securities | Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	99,889	39,354
U.S. government and agency securities | Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	0	0
Asset-backed securities | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	696,572	767,001
Asset-backed securities | Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	0	0
Asset-backed securities | Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	696,572	767,001
Asset-backed securities | Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	0
Municipal bonds | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	35,054	34,962
Municipal bonds | Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	0	0
Municipal bonds | Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	35,054	34,962
Municipal bonds | Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	0	0
Corporate debt securities | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	316,487	313,757
Corporate debt securities | Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	0	0
Corporate debt securities | Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	316,487	313,757
Corporate debt securities | Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	0	0
Agency pass-through certificates | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	911,835	895,963
Agency pass-through certificates | Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	0	0
Agency pass-through certificates | Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	911,835	895,963
Agency pass-through certificates | Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	$ 0	$ 0

Fair Value Measurements - Fai_2

Fair Value Measurements - Fair Value Measured on Nonrecurring Basis (Details) - Nonrecurring - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value disclosure	$ 0	$ 1,592
Loans receivable/Impaired loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value disclosure	0	202
Real estate owned
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value disclosure	0	1,390
Changes measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total gains (losses)	(123)	(593)
Changes measurement | Loans receivable/Impaired loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total gains (losses)	(123)	(89)
Changes measurement | Real estate owned
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total gains (losses)	0	(504)
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value disclosure	0	0
Level 1 | Loans receivable/Impaired loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value disclosure	0	0
Level 1 | Real estate owned
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value disclosure	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value disclosure	0	0
Level 2 | Loans receivable/Impaired loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value disclosure	0	0
Level 2 | Real estate owned
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value disclosure	0	0
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value disclosure	0	1,592
Level 3 | Loans receivable/Impaired loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value disclosure	0	202
Level 3 | Real estate owned
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value disclosure	$ 0	$ 1,390

Fair Value Measurements - Narra

Fair Value Measurements - Narrative (Details) - USD ($)	3 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Sep. 30, 2022
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Available-for-sale securities purchased	$ 115,909,000	$ 0
Proceeds from sales of available-for-sale securities	0	4,510,000
Held-to-maturity securities purchased	0	0
Proceeds from sale of held-to-maturity securities	$ 0	$ 0
Term of contractual due dates of substantially all mortgage-backed securities (in years)	10 years
Accrued interest for available-for-sale securities	$ 7,063,000		$ 5,694,000
Accrued interest for held-to-maturity securities	1,084,000		$ 1,108,000
Consumer loans | Single-family residential
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Foreclosed residential real estate properties held as REO	93,000
Real estate acquired through foreclosure	$ 2,807,000

Fair Value Measurements - Fai_3

Fair Value Measurements - Fair Value by Balance Sheet Grouping (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities, at fair value	$ 2,059,837	$ 2,051,037
Held-to-maturity securities, at amortized cost	453,443	463,299
FHLB and FRB stock	133,073	95,073
Agency pass-through certificates
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities, at amortized cost	453,443	463,299
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities, at fair value	2,059,837	2,051,037
Held-to-maturity securities, at amortized cost	453,443	463,299
Carrying Amount | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	645,862	683,965
Carrying Amount | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
FHLB and FRB stock	133,073	95,073
Time deposits	3,412,203	3,338,043
FHLB advances	3,075,000	2,125,000
Carrying Amount | Level 2 | Client swap program hedges
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other assets	63,383	67,260
Other liabilities	63,383	67,260
Carrying Amount | Level 2 | Commercial loan fair value hedges
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other assets	2,446	2,517
Carrying Amount | Level 2 | Mortgage loan fair value hedges
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other assets	33,986	36,765
Carrying Amount | Level 2 | Borrowings cash flow hedges
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other assets	173,139	179,945
Carrying Amount | Level 2 | U.S. government and agency securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities, at fair value	99,889	39,354
Carrying Amount | Level 2 | Asset-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities, at fair value	696,572	767,001
Carrying Amount | Level 2 | Municipal bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities, at fair value	35,054	34,962
Carrying Amount | Level 2 | Corporate debt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities, at fair value	316,487	313,757
Carrying Amount | Level 2 | Agency pass-through certificates
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities, at fair value	911,835	895,963
Held-to-maturity securities, at amortized cost	453,443	463,299
Carrying Amount | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans receivable	16,993,588	16,113,564
Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities, at fair value	2,059,837	2,051,037
Held-to-maturity securities, at amortized cost	402,055	406,860
Estimated Fair Value | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	645,862	683,965
Estimated Fair Value | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
FHLB and FRB stock	133,073	95,073
Time deposits	3,329,708	3,249,169
FHLB advances	3,067,487	1,940,813
Estimated Fair Value | Level 2 | Client swap program hedges
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other assets	63,383	67,260
Other liabilities	63,383	67,260
Estimated Fair Value | Level 2 | Commercial loan fair value hedges
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other assets	2,446	2,517
Estimated Fair Value | Level 2 | Mortgage loan fair value hedges
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other assets	33,986	36,765
Estimated Fair Value | Level 2 | Borrowings cash flow hedges
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other assets	173,139	179,945
Estimated Fair Value | Level 2 | U.S. government and agency securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities, at fair value	99,889	39,354
Estimated Fair Value | Level 2 | Asset-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities, at fair value	696,572	767,001
Estimated Fair Value | Level 2 | Municipal bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities, at fair value	35,054	34,962
Estimated Fair Value | Level 2 | Corporate debt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities, at fair value	316,487	313,757
Estimated Fair Value | Level 2 | Agency pass-through certificates
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities, at fair value	911,835	895,963
Held-to-maturity securities, at amortized cost	402,055	406,860
Estimated Fair Value | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans receivable	$ 16,310,687	$ 15,417,635

Fair Value Measurements - Inves

Fair Value Measurements - Investments by Contractual Maturity Date (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022
Amortized Cost, Available-for-sale securities
Amortized Cost	$ 2,178,717	$ 2,162,737
Gross Unrealized Gains / Losses, Available-for-sale securities
Gross unrealized gains	1,210	1,308
Gross unrealized loss	(120,090)	(113,008)
Fair Value, Available-for-sale securities
Fair value	$ 2,059,837	$ 2,051,037
Yield, Available-for-sale securities
Yield	3.99%	3.36%
Amortized Cost, Held-to-maturity securities
Held-to-maturity securities	$ 453,443	$ 463,299
Gross Unrealized Gains / Losses, Held-to-maturity securities
Held-to-maturity securities, gross unrealized gains	23	22
Held-to-maturity securities, gross unrealized losses	(51,411)	(56,461)
Fair Value, Held-to-maturity securities
Held-to-maturity securities, fair value	$ 402,055	$ 406,860
Yield, Held-to-maturity securities
Held-to-maturity securities, yield	2.88%	2.88%
Investments	$ 2,632,160	$ 2,626,036
Gross unrealized gains on investments	1,233	1,330
Gross unrealized losses on investments	(171,501)	(169,469)
Total financial assets	$ 2,461,892	$ 2,457,897
Yield on investments	3.80%	3.28%
U.S. government and agency securities
Amortized Cost, Available-for-sale securities
Amortized cost, 1 to 5 years	$ 36,531	$ 40,403
Amortized cost, over 10 years	64,060
Gross Unrealized Gains / Losses, Available-for-sale securities
Gross unrealized gains, 1 to 5 years	0	0
Gross unrealized gains, over 10 years	223
Gross unrealized losses, 1 to 5 years	(925)	(1,049)
Gross unrealized losses, over 10 years	0
Fair Value, Available-for-sale securities
Fair value, 1 to 5 years	35,606	$ 39,354
Fair value, over 10 years	$ 64,283
Yield, Available-for-sale securities
Yield, 1 to 5 years	4.33%	3.03%
Yield, over 10 years	3.90%
Asset-backed securities
Amortized Cost, Available-for-sale securities
Amortized cost, 1 to 5 years	$ 21,033	$ 22,527
Amortized cost, 5 to 10 years	67,783	82,962
Amortized cost, over 10 years	627,579	668,482
Gross Unrealized Gains / Losses, Available-for-sale securities
Gross unrealized gains, 1 to 5 years	0	0
Gross unrealized gains, 5 to 10 years	0	4
Gross unrealized gains, over 10 years	365	783
Gross unrealized losses, 1 to 5 years	(1,524)	(1,141)
Gross unrealized losses, 5 to 10 years	(1,025)	(547)
Gross unrealized losses, over 10 years	(17,639)	(6,069)
Fair Value, Available-for-sale securities
Fair value, 1 to 5 years	19,509	21,386
Fair value, 5 to 10 years	66,758	82,419
Fair value, over 10 years	$ 610,305	$ 663,196
Yield, Available-for-sale securities
Yield, 1 to 5 years	4.58%	3.27%
Yield, 5 to 10 years	5.01%	3.53%
Yield, over 10 years	5.12%	3.86%
Corporate debt securities
Amortized Cost, Available-for-sale securities
Amortized cost, within 1 year	$ 75,000	$ 75,000
Amortized cost, 1 to 5 years	151,531	151,411
Amortized cost, 5 to 10 years	114,116	114,414
Gross Unrealized Gains / Losses, Available-for-sale securities
Gross unrealized gains, within 1 year	29	4
Gross unrealized gains, 1 to 5 years	232	0
Gross unrealized gains, 5 to 10 years	0	0
Gross unrealized losses, Within 1 year	(212)	(200)
Gross unrealized losses, 1 to 5 years	(3,435)	(2,748)
Gross unrealized losses, 5 to 10 years	(20,774)	(24,124)
Fair Value, Available-for-sale securities
Fair value, within 1 year	74,817	74,804
Fair value, 1 to 5 years	148,328	148,663
Fair value, 5 to 10 years	$ 93,342	$ 90,290
Yield, Available-for-sale securities
Yield, within 1 year	5.08%	3.74%
Yield, 1 to 5 years	4.49%	3.59%
Yield, 5 to 10 years	3.87%	3.87%
Municipal bonds due
Amortized Cost, Available-for-sale securities
Amortized cost, 5 to 10 years	$ 5,743	$ 5,751
Amortized cost, over 10 years	29,861	29,871
Gross Unrealized Gains / Losses, Available-for-sale securities
Gross unrealized gains, 5 to 10 years	0	0
Gross unrealized gains, over 10 years	350	400
Gross unrealized losses, 5 to 10 years	(360)	(361)
Gross unrealized losses, over 10 years	(540)	(699)
Fair Value, Available-for-sale securities
Fair value, 5 to 10 years	5,383	5,390
Fair value, over 10 years	$ 29,671	$ 29,572
Yield, Available-for-sale securities
Yield, 5 to 10 years	3%	3%
Yield, over 10 years	5.85%	5.85%
Agency pass-through certificates
Amortized Cost, Available-for-sale securities
Amortized cost, without single maturity date	$ 985,480	$ 971,916
Gross Unrealized Gains / Losses, Available-for-sale securities
Gross unrealized gains, without single maturity date	11	117
Gross unrealized losses, without single maturity date	(73,656)	(76,070)
Fair Value, Available-for-sale securities
Fair value, without single maturity date	$ 911,835	$ 895,963
Yield, Available-for-sale securities
Yield, without single maturity date	2.98%	2.81%
Amortized Cost, Held-to-maturity securities
Held-to-maturity securities	$ 453,443	$ 463,299
Gross Unrealized Gains / Losses, Held-to-maturity securities
Held-to-maturity securities, gross unrealized gains	23	22
Held-to-maturity securities, gross unrealized losses	(51,411)	(56,461)
Fair Value, Held-to-maturity securities
Held-to-maturity securities, fair value	$ 402,055	$ 406,860
Yield, Held-to-maturity securities
Held-to-maturity securities, yield	2.88%	2.88%

Fair Value Measurements - Secur

Fair Value Measurements - Securities in Unrealized Loss Positions (Details) $ in Thousands	Dec. 31, 2022 USD ($) security	Sep. 30, 2022 USD ($) security
Debt Securities, Available-for-sale [Line Items]
Number of debt securities with unrealized loss | security	227	223
Available-for-sale securities
Less than 12 months, unrealized gross losses	$ (101,083)	$ (99,294)
12 months or more, unrealized gross losses	(19,007)	(13,714)
Total unrealized gross losses	(120,090)	(113,008)
Less than 12 months, fair value	1,687,022	1,777,599
12 months or more, fair value	157,300	103,603
Total, fair value	1,844,322	1,881,202
Held-to-maturity securities
Less than 12 months, unrealized gross losses	(51,411)	(56,461)
Less than 12 months, fair value	400,422	405,166
12 months or more, unrealized gross losses	0	0
12 months or more, fair value	0	0
Total unrealized gross losses	(51,411)	(56,461)
Total, fair value	400,422	405,166
Less than 12 months, unrealized gross losses	(152,494)	(155,755)
Less than 12 months, fair value	2,087,444	2,182,765
12 months or more, unrealized gross losses	(19,007)	(13,714)
12 months or more, fair value	157,300	103,603
Total unrealized gross losses	(171,501)	(169,469)
Total fair value	2,244,744	2,286,368
Corporate debt securities
Available-for-sale securities
Less than 12 months, unrealized gross losses	(24,421)	(27,072)
12 months or more, unrealized gross losses	0	0
Total unrealized gross losses	(24,421)	(27,072)
Less than 12 months, fair value	217,278	288,753
12 months or more, fair value	0	0
Total, fair value	217,278	288,753
Municipal bonds due
Available-for-sale securities
Less than 12 months, unrealized gross losses	(900)	(1,061)
12 months or more, unrealized gross losses	0	0
Total unrealized gross losses	(900)	(1,061)
Less than 12 months, fair value	14,704	14,561
12 months or more, fair value	0	0
Total, fair value	14,704	14,561
U.S. government and agency securities
Available-for-sale securities
Less than 12 months, unrealized gross losses	(120)	(1,049)
12 months or more, unrealized gross losses	(805)	0
Total unrealized gross losses	(925)	(1,049)
Less than 12 months, fair value	28,002	39,354
12 months or more, fair value	7,604	0
Total, fair value	35,606	39,354
Asset-backed securities
Available-for-sale securities
Less than 12 months, unrealized gross losses	(16,304)	(6,374)
12 months or more, unrealized gross losses	(3,884)	(1,383)
Total unrealized gross losses	(20,188)	(7,757)
Less than 12 months, fair value	593,310	601,248
12 months or more, fair value	72,112	50,070
Total, fair value	665,422	651,318
Mortgage-backed securities
Available-for-sale securities
Less than 12 months, unrealized gross losses	(59,338)	(63,738)
12 months or more, unrealized gross losses	(14,318)	(12,331)
Total unrealized gross losses	(73,656)	(76,069)
Less than 12 months, fair value	833,728	833,683
12 months or more, fair value	77,584	53,533
Total, fair value	$ 911,312	$ 887,216

Derivatives and Hedging Activ_3

Derivatives and Hedging Activities - Summary of Fair Value, Notional Amount and Balance Sheet Classification (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022
Other assets
Derivatives, Fair Value [Line Items]
Notional amount	$ 2,093,443	$ 2,100,885
Derivative assets, fair value	272,955	286,487
Other liabilities
Derivatives, Fair Value [Line Items]
Notional amount	583,782	588,676
Derivative liabilities, fair value	63,383	67,260
Client swap program hedges | Other assets
Derivatives, Fair Value [Line Items]
Notional amount	583,782	588,676
Derivative assets, fair value	63,383	67,260
Client swap program hedges | Other liabilities
Derivatives, Fair Value [Line Items]
Notional amount	583,782	588,676
Derivative liabilities, fair value	63,383	67,260
Commercial loan fair value hedges | Other assets
Derivatives, Fair Value [Line Items]
Notional amount	39,661	42,209
Derivative assets, fair value	2,447	2,517
Commercial loan fair value hedges | Other liabilities
Derivatives, Fair Value [Line Items]
Notional amount	0	0
Derivative liabilities, fair value	0	0
Mortgage loan fair value hedges
Derivatives, Fair Value [Line Items]
Notional amount	470,000
Mortgage loan fair value hedges | Other assets
Derivatives, Fair Value [Line Items]
Notional amount	470,000	470,000
Derivative assets, fair value	33,986	36,765
Mortgage loan fair value hedges | Other liabilities
Derivatives, Fair Value [Line Items]
Notional amount	0	0
Derivative liabilities, fair value	0	0
Borrowings cash flow hedges | Other assets
Derivatives, Fair Value [Line Items]
Notional amount	1,000,000	1,000,000
Derivative assets, fair value	173,139	179,945
Borrowings cash flow hedges | Other liabilities
Derivatives, Fair Value [Line Items]
Notional amount	0	0
Derivative liabilities, fair value	$ 0	$ 0

Derivatives and Hedging Activ_4

Derivatives and Hedging Activities - Impact of Fair Value Hedge Accounting on the Carrying Value of the Hedged Items (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022
Derivatives, Fair Value [Line Items]
Carrying value of hedged items	$ 1,131,282	$ 1,159,496
Cumulative gain (loss) fair value hedge adjustment included in carrying amount of hedged items	(35,958)	(39,090)
Loans Receivable
Derivatives, Fair Value [Line Items]
Carrying value of hedged items	1,131,282	1,159,496
Cumulative gain (loss) fair value hedge adjustment included in carrying amount of hedged items	(35,958)	(39,090)
Other liabilities
Derivatives, Fair Value [Line Items]
Notional amount	583,782	588,676
Mortgage loan fair value hedges
Derivatives, Fair Value [Line Items]
Cumulative gain (loss) fair value hedge adjustment included in carrying amount of hedged items	(33,423)	(36,458)
Notional amount	470,000
Mortgage loan fair value hedges | Loans Receivable
Derivatives, Fair Value [Line Items]
Carrying value of hedged items	1,094,211	1,119,975
Mortgage loan fair value hedges | Other liabilities
Derivatives, Fair Value [Line Items]
Notional amount	0	0
Commercial loan fair value hedges
Derivatives, Fair Value [Line Items]
Cumulative gain (loss) fair value hedge adjustment included in carrying amount of hedged items	(2,535)	(2,632)
Commercial loan fair value hedges | Loans Receivable
Derivatives, Fair Value [Line Items]
Carrying value of hedged items	37,071	39,521
Commercial loan fair value hedges | Other liabilities
Derivatives, Fair Value [Line Items]
Notional amount	$ 0	$ 0

Derivatives and Hedging Activ_5

Derivatives and Hedging Activities - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Derivative [Line Items]
Gain (loss) recognized on cash flow hedges	$ 0	$ 0
Interest Rate Swap | Minimum
Derivative [Line Items]
Derivative, maturities	2 years
Interest Rate Swap | Maximum
Derivative [Line Items]
Derivative, maturities	8 years
Interest Rate Swap | Weighted average
Derivative [Line Items]
Derivative, maturities	6 years 3 months 18 days

Derivatives and Hedging Activ_6

Derivatives and Hedging Activities - Impact of Derivative Instruments on AOCI (Details) - Cash flow hedging - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Derivative [Line Items]
Total pre-tax gain/(loss) recognized in AOCI	$ (6,806)	$ 6,446
Pay fixed/receive floating swaps on borrowings cash flow hedges
Derivative [Line Items]
Pay fixed/receive floating swaps on borrowings cash flow hedges	$ (6,806)	$ 6,446

Derivatives and Hedging Activ_7

Derivatives and Hedging Activities - Gains/(Losses) on Derivative Instruments in Fair Value and Cash Flow Accounting Hedging Relationships (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Derivative Instruments, Gain (Loss) [Line Items]
Interest income/(expense), including the effects of fair value and cash flow hedges	$ 203,946	$ 138,509
Interest income/(expense), including the effects of fair value and cash flow hedges	(18,974)	(7,843)
Gain/(loss) on cash flow hedging relationships:
Gain (loss) recognized on cash flow hedges	0	0
Interest rate contracts | Interest income on loans receivable | Fair value hedging
Gain/(loss) on fair value hedging relationships:
Amounts related to interest settlements on derivatives	3,167	(1,371)
Recognized on derivatives	(2,849)	4,500
Recognized on hedged items	3,132	(4,475)
Net income/(expense) recognized on fair value hedges	3,450	(1,346)
Interest rate contracts | Interest expense on FHLB advances | Cash flow hedging
Gain/(loss) on cash flow hedging relationships:
Amounts related to interest settlements on derivatives	7,274	2,021
Amount of derivative gain/(loss) reclassified from AOCI into interest income/expense	0	0
Gain (loss) recognized on cash flow hedges	$ 7,274	$ 2,021

Derivatives and Hedging Activ_8

Derivatives and Hedging Activities - Impact of Client Swap Program that are Not Designated in Accounting Hedges (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Client swap program hedges
Derivative [Line Items]
Derivative instruments not designated as hedging instruments, gain (loss), net	$ 0	$ 0
Other noninterest income | Pay fixed/receive floating swap
Derivative [Line Items]
Derivative instruments not designated as hedging instruments, gain (loss), net	(3,878)	5,039
Other noninterest income | Receive fixed/pay floating swap
Derivative [Line Items]
Derivative instruments not designated as hedging instruments, gain (loss), net	$ 3,878	$ (5,039)

Revenue from Contracts with C_2

Revenue from Contracts with Customers (Details)	3 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Revenue from Contract with Customer [Abstract]
Revenue streams percentage, contract with customer	3.90%	5.60%

Commitment and Contingencies (D

Commitment and Contingencies (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans in process	$ 2,997,839	$ 3,006,023
Off-balance-sheet credit reserve	31,500	32,500
Financing Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans in process	$ 4,822,769	$ 4,947,570