$CFFN
Capitol Federal Financial, Inc. Stock $cffn

$cffn Overview Financials Valuation SEC Filings Company Website

2024 Q4 Form 10-K Financial Statement

#000149090624000035 Filed on November 27, 2024

Income Statement

Concept	2024 Q4	2024 Q3	2024
Revenue			$15.30M
YoY Change			-13.07%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development			$20.32M
YoY Change			-13.24%
% of Gross Profit
Depreciation & Amortization
YoY Change
% of Gross Profit
Operating Expenses			$20.32M
YoY Change			-13.24%
Operating Profit
YoY Change
Interest Expense
YoY Change
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income			$54.10M
YoY Change			-138.94%
Income Tax			$16.09M
% Of Pretax Income			29.75%
Net Earnings			$38.01M
YoY Change			-137.39%
Net Earnings / Revenue			248.43%
Basic Earnings Per Share			$0.29
Diluted Earnings Per Share			$0.29
COMMON SHARES
Basic Shares Outstanding	132.8M shares	132.7M shares	130.7M shares
Diluted Shares Outstanding			130.7M shares

Balance Sheet

Concept	2024 Q3	2024
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$217.3M
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$91.46M	$91.46M
YoY Change	-0.07%	-11.06%
Goodwill	$9.324M
YoY Change	0.0%
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets	$21.98M	$21.98M
YoY Change	-25.76%	-25.76%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$9.528B	$9.528B
YoY Change	-6.39%	-6.39%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$124.0M	$124.0M
YoY Change	-11.48%	-3.49%
Accrued Expenses
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$124.0M	$124.0M
YoY Change	-11.48%	-11.48%
LONG-TERM LIABILITIES
Long-Term Debt
YoY Change
Other Long-Term Liabilities	$61.80M	$61.80M
YoY Change	-1.89%	-1.89%
Total Long-Term Liabilities	$61.80M	$61.80M
YoY Change	-1.89%	-1.89%
TOTAL LIABILITIES
Total Short-Term Liabilities	$124.0M	$124.0M
Total Long-Term Liabilities	$61.80M	$61.80M
Total Liabilities	$8.495B	$8.495B
YoY Change	-6.99%	-6.99%
SHAREHOLDERS EQUITY
Retained Earnings	-$111.1M
YoY Change	6.25%
Common Stock	$1.148B
YoY Change	-1.7%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$1.032B	$1.032B
YoY Change
Total Liabilities & Shareholders Equity	$9.528B	$9.528B
YoY Change	-6.39%	-6.39%

Cashflow Statement

Concept	2024 Q4	2024 Q3	2024
OPERATING ACTIVITIES
Net Income			$38.01M
YoY Change			-137.39%
Depreciation, Depletion And Amortization
YoY Change
Cash From Operating Activities			$31.18M
YoY Change			-34.39%
INVESTING ACTIVITIES
Capital Expenditures			$7.184M
YoY Change			14.38%
Acquisitions
YoY Change
Other Investing Activities
YoY Change
Cash From Investing Activities			$629.1M
YoY Change			-291.16%
FINANCING ACTIVITIES
Cash Dividend Paid			$44.52M
YoY Change			-46.47%
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities			-$688.6M
YoY Change			-244.06%
NET CHANGE
Cash From Operating Activities			$31.18M
Cash From Investing Activities			$629.1M
Cash From Financing Activities			-$688.6M
Net Change In Cash			-$28.30M
YoY Change			-114.41%
FREE CASH FLOW
Cash From Operating Activities			$31.18M
Capital Expenditures			$7.184M
Free Cash Flow			$24.00M
YoY Change			-41.82%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2024	us-gaap	Interest Income Securities Mortgage Backed InterestIncomeSecuritiesMortgageBacked	33650000	usd
CY2023	us-gaap	Interest Income Securities Mortgage Backed InterestIncomeSecuritiesMortgageBacked	18520000	usd
CY2022	us-gaap	Interest Income Securities Mortgage Backed InterestIncomeSecuritiesMortgageBacked	19406000	usd
CY2023	us-gaap	Interest Income Debt Securities Operating InterestIncomeDebtSecuritiesOperating	3565000	usd
CY2024	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	376843000	usd
CY2023	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	359789000	usd
CY2022	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	279540000	usd
CY2024	us-gaap	Interest Expense Borrowings InterestExpenseBorrowings	75233000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	-101659000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	84453000	usd
CY2023	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	-51000	usd
CY2022	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	45000	usd
CY2023	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-101608000	usd
CY2023	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	-101608000	usd
CY2024	dei	Entity Central Index Key EntityCentralIndexKey	0001490906
CY2024	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2024	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2024	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2024	dei	Entity Small Business EntitySmallBusiness	false
CY2024	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2024	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
CY2024	dei	Document Fin Stmt Error Correction Flag DocumentFinStmtErrorCorrectionFlag	false
CY2024	dei	Entity Shell Company EntityShellCompany	false
CY2024Q1	dei	Entity Public Float EntityPublicFloat	772200000	usd
CY2024Q4	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	132774365	shares
CY2024Q3	us-gaap	Income Tax Receivable IncomeTaxReceivable	359000	usd
CY2023Q3	us-gaap	Income Tax Receivable IncomeTaxReceivable	8531000	usd
CY2024Q3	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	21978000	usd
CY2023Q3	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	29605000	usd
CY2024Q3	us-gaap	Other Assets OtherAssets	331722000	usd
CY2023Q3	us-gaap	Other Assets OtherAssets	336044000	usd
CY2024Q3	us-gaap	Assets Assets	9527608000	usd
CY2023Q3	us-gaap	Assets Assets	10177461000	usd
CY2024Q3	us-gaap	Deposits Domestic DepositsDomestic	6129982000	usd
CY2023Q3	us-gaap	Deposits Domestic DepositsDomestic	6051220000	usd
CY2024Q3	us-gaap	Debt Longterm And Shortterm Combined Amount DebtLongtermAndShorttermCombinedAmount	2179564000	usd
CY2023Q3	us-gaap	Debt Longterm And Shortterm Combined Amount DebtLongtermAndShorttermCombinedAmount	2879125000	usd
CY2024Q3	us-gaap	Advance Payments By Borrowers For Taxes And Insurance AdvancePaymentsByBorrowersForTaxesAndInsurance	61801000	usd
CY2023Q3	us-gaap	Advance Payments By Borrowers For Taxes And Insurance AdvancePaymentsByBorrowersForTaxesAndInsurance	62993000	usd
CY2024Q3	us-gaap	Accounts Payable And Other Accrued Liabilities AccountsPayableAndOtherAccruedLiabilities	123991000	usd
CY2023Q3	us-gaap	Accounts Payable And Other Accrued Liabilities AccountsPayableAndOtherAccruedLiabilities	140069000	usd
CY2024Q3	us-gaap	Liabilities Liabilities	8495338000	usd
CY2023Q3	us-gaap	Liabilities Liabilities	9133407000	usd
CY2024Q3	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.01
CY2023Q3	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.01
CY2024Q3	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	100000000	shares
CY2023Q3	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	100000000	shares
CY2024Q3	us-gaap	Preferred Stock Value PreferredStockValue	0	usd
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CY2024Q3	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	1146851000	usd
CY2023Q3	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	1166643000	usd
CY2024Q3	cffn	Unearned Esop Shares Cost UnearnedESOPSharesCost	26431000	usd
CY2023Q3	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	-104565000	usd
CY2024Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	21627000	usd
CY2023Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	8700000	usd
CY2024Q3	us-gaap	Stockholders Equity StockholdersEquity	1032270000	usd
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CY2024Q3	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	9527608000	usd
CY2023Q3	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	10177461000	usd
CY2024	us-gaap	Interest And Fee Income Loans And Leases InterestAndFeeIncomeLoansAndLeases	308707000	usd
CY2023	us-gaap	Interest And Fee Income Loans And Leases InterestAndFeeIncomeLoansAndLeases	280087000	usd
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CY2024	us-gaap	Dividend Income Operating DividendIncomeOperating	10009000	usd
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CY2022	us-gaap	Interest Income Debt Securities Operating InterestIncomeDebtSecuritiesOperating	3268000	usd
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CY2022	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	192594000	usd
CY2024	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	1259000	usd
CY2024	dei	Document Type DocumentType	10-K
CY2024	dei	Document Period End Date DocumentPeriodEndDate	2024-09-30
CY2024	us-gaap	Interest Expense Deposits InterestExpenseDeposits	139549000	usd
CY2023	us-gaap	Interest Expense Deposits InterestExpenseDeposits	82267000	usd
CY2022	us-gaap	Interest Expense Deposits InterestExpenseDeposits	34456000	usd
CY2023	us-gaap	Interest Expense Borrowings InterestExpenseBorrowings	124250000	usd
CY2022	us-gaap	Interest Expense Borrowings InterestExpenseBorrowings	52490000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	84453000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	84453000	usd
CY2024	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	33000	usd
CY2024	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	37977000	usd
CY2022	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	84408000	usd
CY2023	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	133556864	shares
CY2022	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	135700447	shares
CY2022	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	0	shares
CY2024	us-gaap	Interest Income Debt Securities Operating InterestIncomeDebtSecuritiesOperating	8749000	usd
CY2024	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2024
CY2024	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
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CY2024	dei	Document Annual Report DocumentAnnualReport	true
CY2024	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--09-30
CY2024	dei	Document Transition Report DocumentTransitionReport	false
CY2024	dei	Entity File Number EntityFileNumber	001-34814
CY2024	dei	Entity Registrant Name EntityRegistrantName	Capitol Federal Financial, Inc.
CY2024	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	MD
CY2024	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	27-2631712
CY2024	dei	Entity Address Address Line1 EntityAddressAddressLine1	700 South Kansas Avenue,
CY2024	dei	Entity Address City Or Town EntityAddressCityOrTown	Topeka,
CY2024	dei	Entity Address State Or Province EntityAddressStateOrProvince	KS
CY2024	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	66603
CY2024	dei	City Area Code CityAreaCode	785
CY2024	dei	Local Phone Number LocalPhoneNumber	235-1341
CY2024	dei	Security12b Title Security12bTitle	Common Stock, par value $0.01 per share
CY2024	dei	Trading Symbol TradingSymbol	CFFN
CY2024	dei	Security Exchange Name SecurityExchangeName	NASDAQ
CY2024	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2024	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
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CY2024Q3	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	-111104000	usd
CY2024	us-gaap	Interest Income Deposits With Financial Institutions InterestIncomeDepositsWithFinancialInstitutions	15728000	usd
CY2023	us-gaap	Interest Income Deposits With Financial Institutions InterestIncomeDepositsWithFinancialInstitutions	43796000	usd
CY2022	us-gaap	Interest Income Deposits With Financial Institutions InterestIncomeDepositsWithFinancialInstitutions	18304000	usd
CY2024	us-gaap	Interest Expense Operating InterestExpenseOperating	214782000	usd
CY2023	us-gaap	Interest Expense Operating InterestExpenseOperating	206517000	usd
CY2022	us-gaap	Interest Expense Operating InterestExpenseOperating	86946000	usd
CY2023	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	6838000	usd
CY2022	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	-4630000	usd
CY2024	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	160802000	usd
CY2023	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	146434000	usd
CY2022	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	197224000	usd
CY2024	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-13345000	usd
CY2023	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-192622000	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	0	usd
CY2024	us-gaap	Noninterest Income Other NoninterestIncomeOther	4770000	usd
CY2023	us-gaap	Noninterest Income Other NoninterestIncomeOther	4935000	usd
CY2022	us-gaap	Noninterest Income Other NoninterestIncomeOther	6085000	usd
CY2024	us-gaap	Noninterest Income NoninterestIncome	5244000	usd
CY2023	us-gaap	Noninterest Income NoninterestIncome	-171455000	usd
CY2022	us-gaap	Noninterest Income NoninterestIncome	22830000	usd
CY2024	us-gaap	Labor And Related Expense LaborAndRelatedExpense	52272000	usd
CY2023	us-gaap	Labor And Related Expense LaborAndRelatedExpense	51491000	usd
CY2022	us-gaap	Labor And Related Expense LaborAndRelatedExpense	56600000	usd
CY2024	us-gaap	Communications And Information Technology CommunicationsAndInformationTechnology	20324000	usd
CY2023	us-gaap	Communications And Information Technology CommunicationsAndInformationTechnology	23425000	usd
CY2022	us-gaap	Communications And Information Technology CommunicationsAndInformationTechnology	18311000	usd
CY2024	us-gaap	Occupancy Net OccupancyNet	13558000	usd
CY2023	us-gaap	Occupancy Net OccupancyNet	14236000	usd
CY2022	us-gaap	Occupancy Net OccupancyNet	14370000	usd
CY2024	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	6052000	usd
CY2023	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	4456000	usd
CY2022	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	3020000	usd
CY2024	cffn	Regulatory And Professional Fees RegulatoryAndProfessionalFees	5743000	usd
CY2023	cffn	Regulatory And Professional Fees RegulatoryAndProfessionalFees	6039000	usd
CY2022	cffn	Regulatory And Professional Fees RegulatoryAndProfessionalFees	6192000	usd
CY2024	us-gaap	Advertising Expense AdvertisingExpense	4264000	usd
CY2023	us-gaap	Advertising Expense AdvertisingExpense	4305000	usd
CY2022	us-gaap	Advertising Expense AdvertisingExpense	5178000	usd
CY2024	cffn	Deposit And Loan Transaction Costs DepositAndLoanTransactionCosts	2719000	usd
CY2023	cffn	Deposit And Loan Transaction Costs DepositAndLoanTransactionCosts	2694000	usd
CY2022	cffn	Deposit And Loan Transaction Costs DepositAndLoanTransactionCosts	2797000	usd
CY2024	us-gaap	Supplies And Postage Expense SuppliesAndPostageExpense	1691000	usd
CY2023	us-gaap	Supplies And Postage Expense SuppliesAndPostageExpense	2499000	usd
CY2022	us-gaap	Supplies And Postage Expense SuppliesAndPostageExpense	1951000	usd
CY2024	us-gaap	Other Noninterest Expense OtherNoninterestExpense	5320000	usd
CY2023	us-gaap	Other Noninterest Expense OtherNoninterestExpense	4789000	usd
CY2022	us-gaap	Other Noninterest Expense OtherNoninterestExpense	4432000	usd
CY2024	us-gaap	Noninterest Expense NoninterestExpense	111943000	usd
CY2023	us-gaap	Noninterest Expense NoninterestExpense	113934000	usd
CY2022	us-gaap	Noninterest Expense NoninterestExpense	112851000	usd
CY2024	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	54103000	usd
CY2023	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-138955000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	107203000	usd
CY2024	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	16093000	usd
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-37296000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	22750000	usd
CY2024	us-gaap	Net Income Loss NetIncomeLoss	38010000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	-101659000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	84453000	usd
CY2024	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.29
CY2023	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.76
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.62
CY2024	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.29
CY2023	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.76
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.62
CY2024	us-gaap	Net Income Loss NetIncomeLoss	38010000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	-101659000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	84453000	usd
CY2024	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	7133000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	2696000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	-51565000	usd
CY2024	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	22362000	usd
CY2023	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	8355000	usd
CY2022	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-159770000	usd
CY2024	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	383000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Writedown Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForWritedownOfSecuritiesTax	-47000000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Writedown Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForWritedownOfSecuritiesTax	0	usd
CY2024	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	1188000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Writedown Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForWritedownOfSecuritiesNetOfTax	145622000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Writedown Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForWritedownOfSecuritiesNetOfTax	0	usd
CY2024	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax	-701000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax	1923000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax	8177000	usd
CY2024	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	-2135000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	5957000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	25339000	usd
CY2024	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax	-1967000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax	-1808000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax	1647000	usd
CY2024	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	6112000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	5601000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	-5103000	usd
CY2024	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	50937000	usd
CY2023	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	52674000	usd
CY2022	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-44875000	usd
CY2021Q3	us-gaap	Stockholders Equity StockholdersEquity	1242273000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-129328000	usd
CY2022	us-gaap	Stock Issued During Period Value Employee Stock Ownership Plan StockIssuedDuringPeriodValueEmployeeStockOwnershipPlan	1740000	usd
CY2022	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	-6000	usd
CY2022	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	498000	usd
CY2022	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.76
CY2022	us-gaap	Dividends Cash DividendsCash	103131000	usd
CY2022Q3	us-gaap	Stockholders Equity StockholdersEquity	1096499000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	-101659000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	154333000	usd
CY2023	us-gaap	Stock Issued During Period Value Employee Stock Ownership Plan StockIssuedDuringPeriodValueEmployeeStockOwnershipPlan	1179000	usd
CY2023	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	327000	usd
CY2023	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	23453000	usd
CY2023	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.62
CY2023	us-gaap	Dividends Cash DividendsCash	83172000	usd
CY2023Q3	us-gaap	Stockholders Equity StockholdersEquity	1044054000	usd
CY2024	us-gaap	Net Income Loss NetIncomeLoss	38010000	usd
CY2024	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	12927000	usd
CY2024	us-gaap	Stock Issued During Period Value Employee Stock Ownership Plan StockIssuedDuringPeriodValueEmployeeStockOwnershipPlan	927000	usd
CY2024	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	-9000	usd
CY2024	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	358000	usd
CY2024	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	19448000	usd
CY2024	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.34
CY2024	us-gaap	Dividends Cash DividendsCash	44522000	usd
CY2024Q3	us-gaap	Stockholders Equity StockholdersEquity	1032270000	usd
CY2024	us-gaap	Net Income Loss NetIncomeLoss	38010000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	-101659000	usd
CY2024	us-gaap	Dividend Income Operating DividendIncomeOperating	10009000	usd
CY2023	us-gaap	Dividend Income Operating DividendIncomeOperating	13821000	usd
CY2022	us-gaap	Dividend Income Operating DividendIncomeOperating	10031000	usd
CY2024	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	1259000	usd
CY2023	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	6838000	usd
CY2022	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	-4630000	usd
CY2024	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	712000	usd
CY2023	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	1217000	usd
CY2022	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	1088000	usd
CY2024	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	725000	usd
CY2023	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	1222000	usd
CY2022	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	1113000	usd
CY2024	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	8182000	usd
CY2023	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-3016000	usd
CY2022	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-4967000	usd
CY2024	us-gaap	Depreciation Nonproduction DepreciationNonproduction	7929000	usd
CY2023	us-gaap	Depreciation Nonproduction DepreciationNonproduction	9039000	usd
CY2022	us-gaap	Depreciation Nonproduction DepreciationNonproduction	9365000	usd
CY2024	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	774000	usd
CY2023	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1069000	usd
CY2022	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1372000	usd
CY2024	cffn	Amortization Of Deferred Amounts Related To Fhlb Advances Net AmortizationOfDeferredAmountsRelatedToFhlbAdvancesNet	1529000	usd
CY2023	cffn	Amortization Of Deferred Amounts Related To Fhlb Advances Net AmortizationOfDeferredAmountsRelatedToFhlbAdvancesNet	1643000	usd
CY2022	cffn	Amortization Of Deferred Amounts Related To Fhlb Advances Net AmortizationOfDeferredAmountsRelatedToFhlbAdvancesNet	1804000	usd
CY2024	us-gaap	Employee Stock Ownership Plan Esop Compensation Expense EmployeeStockOwnershipPlanESOPCompensationExpense	927000	usd
CY2023	us-gaap	Employee Stock Ownership Plan Esop Compensation Expense EmployeeStockOwnershipPlanESOPCompensationExpense	1179000	usd
CY2022	us-gaap	Employee Stock Ownership Plan Esop Compensation Expense EmployeeStockOwnershipPlanESOPCompensationExpense	1740000	usd
CY2024	us-gaap	Share Based Compensation ShareBasedCompensation	358000	usd
CY2023	us-gaap	Share Based Compensation ShareBasedCompensation	327000	usd
CY2022	us-gaap	Share Based Compensation ShareBasedCompensation	498000	usd
CY2024	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	3546000	usd
CY2023	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-45520000	usd
CY2022	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	2047000	usd
CY2024	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-13345000	usd
CY2023	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-192622000	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	0	usd
CY2024	us-gaap	Increase Decrease Cash Collateral From Counterparties IncreaseDecreaseCashCollateralFromCounterparties	-11850000	usd
CY2023	us-gaap	Increase Decrease Cash Collateral From Counterparties IncreaseDecreaseCashCollateralFromCounterparties	1940000	usd
CY2022	us-gaap	Increase Decrease Cash Collateral From Counterparties IncreaseDecreaseCashCollateralFromCounterparties	12050000	usd
CY2024	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-8227000	usd
CY2023	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-2528000	usd
CY2022	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-6661000	usd
CY2024	us-gaap	Increase Decrease In Income Taxes Payable Net Of Income Taxes Receivable IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable	8139000	usd
CY2023	us-gaap	Increase Decrease In Income Taxes Payable Net Of Income Taxes Receivable IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable	-7303000	usd
CY2022	us-gaap	Increase Decrease In Income Taxes Payable Net Of Income Taxes Receivable IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable	-2197000	usd
CY2024	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-22831000	usd
CY2023	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-4372000	usd
CY2022	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-10823000	usd
CY2024	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	31184000	usd
CY2023	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	47531000	usd
CY2022	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	97301000	usd
CY2024	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	1176645000	usd
CY2023	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	0	usd
CY2022	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	88026000	usd
CY2024	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	455110000	usd
CY2023	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	186860000	usd
CY2022	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	323025000	usd
CY2024	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	1272512000	usd
CY2023	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	0	usd
CY2022	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	0	usd
CY2024	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	19548000	usd
CY2023	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	358491000	usd
CY2022	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	302243000	usd
CY2024	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	0	usd
CY2023	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	354760000	usd
CY2022	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	319415000	usd
CY2024	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	-63626000	usd
CY2023	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	520229000	usd
CY2022	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	381561000	usd
CY2024	us-gaap	Proceeds From Sale Of Loans Receivable ProceedsFromSaleOfLoansReceivable	0	usd
CY2023	us-gaap	Proceeds From Sale Of Loans Receivable ProceedsFromSaleOfLoansReceivable	5563000	usd
CY2022	us-gaap	Proceeds From Sale Of Loans Receivable ProceedsFromSaleOfLoansReceivable	0	usd
CY2024	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	7184000	usd
CY2023	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	6281000	usd
CY2022	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	5557000	usd
CY2024	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	464000	usd
CY2023	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	533000	usd
CY2022	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	692000	usd
CY2024	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	629000	usd
CY2023	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	0	usd
CY2022	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	0	usd
CY2024	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	1049000	usd
CY2023	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	720000	usd
CY2022	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	1023000	usd
CY2024	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	629109000	usd
CY2023	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-329103000	usd
CY2022	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-167576000	usd
CY2024	us-gaap	Payments Of Dividends PaymentsOfDividends	44522000	usd
CY2023	us-gaap	Payments Of Dividends PaymentsOfDividends	83172000	usd
CY2022	us-gaap	Payments Of Dividends PaymentsOfDividends	103131000	usd
CY2024	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	78762000	usd
CY2023	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	-143646000	usd
CY2022	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	-402530000	usd
CY2024	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	350100000	usd
CY2023	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	4293870000	usd
CY2022	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	1454402000	usd
CY2024	cffn	Repayments On Borrowings RepaymentsOnBorrowings	1052291000	usd
CY2023	cffn	Repayments On Borrowings RepaymentsOnBorrowings	3548542000	usd
CY2022	cffn	Repayments On Borrowings RepaymentsOnBorrowings	906902000	usd
CY2024	us-gaap	Increase Decrease In Advance Payments By Borrowers For Taxes And Insurance IncreaseDecreaseInAdvancePaymentsByBorrowersForTaxesAndInsurance	-1192000	usd
CY2023	us-gaap	Increase Decrease In Advance Payments By Borrowers For Taxes And Insurance IncreaseDecreaseInAdvancePaymentsByBorrowersForTaxesAndInsurance	-17074000	usd
CY2022	us-gaap	Increase Decrease In Advance Payments By Borrowers For Taxes And Insurance IncreaseDecreaseInAdvancePaymentsByBorrowersForTaxesAndInsurance	7338000	usd
CY2024	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	19448000	usd
CY2023	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	23453000	usd
CY2022	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	usd
CY2024	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-688591000	usd
CY2023	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	477983000	usd
CY2022	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	49177000	usd
CY2024	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-28298000	usd
CY2023	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	196411000	usd
CY2022	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-21098000	usd
CY2023Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	245605000	usd
CY2022Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	49194000	usd
CY2021Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	70292000	usd
CY2024Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	217307000	usd
CY2023Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	245605000	usd
CY2022Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	49194000	usd
CY2024	us-gaap	Income Taxes Paid IncomeTaxesPaid	6017000	usd
CY2023	us-gaap	Income Taxes Paid IncomeTaxesPaid	5424000	usd
CY2022	us-gaap	Income Taxes Paid IncomeTaxesPaid	13559000	usd
CY2024	us-gaap	Interest Paid Net InterestPaidNet	224701000	usd
CY2023	us-gaap	Interest Paid Net InterestPaidNet	188908000	usd
CY2022	us-gaap	Interest Paid Net InterestPaidNet	83833000	usd
CY2024	us-gaap	Nature Of Operations NatureOfOperations	Capitol Federal Financial, Inc. (the "Company") provides a full range of retail banking services through its wholly-owned subsidiary, Capitol Federal Savings Bank (the "Bank"), a federal savings bank, which has 44 traditional and four in-store banking offices serving primarily the metropolitan areas of Topeka, Wichita, Lawrence, Manhattan, Emporia and Salina, Kansas and portions of the Kansas City metropolitan area. The Bank emphasizes mortgage lending, primarily originating one- to four-family loans, and providing personal retail financial services, along with offering commercial banking and lending products.
CY2024Q3	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	0	usd
CY2023Q3	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	0	usd
CY2024Q3	us-gaap	Debt Securities Available For Sale Accrued Interest After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLoss	4800000	usd
CY2023Q3	us-gaap	Debt Securities Available For Sale Accrued Interest After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLoss	3100000	usd
CY2024Q3	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	0	usd
CY2023Q3	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	0	usd
CY2024Q3	us-gaap	Financing Receivable Accrued Interest After Allowance For Credit Loss FinancingReceivableAccruedInterestAfterAllowanceForCreditLoss	26300000	usd
CY2023Q3	us-gaap	Financing Receivable Accrued Interest After Allowance For Credit Loss FinancingReceivableAccruedInterestAfterAllowanceForCreditLoss	25000000.0	usd
CY2024	us-gaap	Derivatives Methods Of Accounting Hedging Derivatives DerivativesMethodsOfAccountingHedgingDerivatives	The Company uses interest rate swaps as part of its interest rate risk management strategy to hedge the variable cash outflows associated with certain borrowings. Interest rate swaps are carried at fair value in the Company's consolidated financial statements. For interest rate swaps that are designated and qualify as cash flow hedges, changes in the fair value of such agreements are recorded in AOCI and are subsequently reclassified into interest expense in the period that interest on the borrowings affects earnings. Effectiveness is assessed using regression analysis. At the inception of a hedge, the Company documents certain items, including the relationship between the hedging instrument and the hedged item, the risk management objective and the nature of the risk being hedged, a description of how effectiveness will be measured and an evaluation of hedged transaction effectiveness.
CY2024	us-gaap	Net Income Loss NetIncomeLoss	38010000	usd
CY2024	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	37977000	usd
CY2022	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	84408000	usd
CY2024	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	130670780	shares
CY2024	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	0	shares
CY2023	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	0	shares
CY2024	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	130670780	shares
CY2023	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	133556864	shares
CY2022	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	135700447	shares
CY2024	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.29
CY2023	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.76
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.62
CY2024	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.29
CY2023	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.76
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.62
CY2024	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	326308	shares
CY2023	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	369421	shares
CY2022	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	516603	shares
CY2024Q3	us-gaap	Debt Securities Available For Sale Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss	829852000	usd
CY2024Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	27113000	usd
CY2024Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	699000	usd
CY2024Q3	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest DebtSecuritiesAvailableForSaleExcludingAccruedInterest	856266000	usd
CY2023Q3	us-gaap	Debt Securities Available For Sale Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss	1385992000	usd
CY2023Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	113000	usd
CY2023Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	1623000	usd
CY2023Q3	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest DebtSecuritiesAvailableForSaleExcludingAccruedInterest	1384482000	usd
CY2024Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	10997000	usd
CY2024Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	44000	usd
CY2024Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	6307000	usd
CY2024Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	655000	usd
CY2023Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	6179000	usd
CY2023Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	109000	usd
CY2023Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	62751000	usd
CY2023Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	1514000	usd
CY2024Q3	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	10000000	usd
CY2024Q3	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	10000000	usd
CY2024Q3	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	63077000	usd
CY2024Q3	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	62693000	usd
CY2024Q3	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	73077000	usd
CY2024Q3	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate	72693000	usd
CY2024Q3	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost	756775000	usd
CY2024Q3	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	783573000	usd
CY2024Q3	us-gaap	Debt Securities Available For Sale Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss	829852000	usd
CY2024Q3	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest DebtSecuritiesAvailableForSaleExcludingAccruedInterest	856266000	usd
CY2024	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	8747000	usd
CY2023	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	3538000	usd
CY2022	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	3234000	usd
CY2024	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	2000	usd
CY2023	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	27000	usd
CY2022	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	34000	usd
CY2024	us-gaap	Interest And Dividend Income Securities InterestAndDividendIncomeSecurities	8749000	usd
CY2023	us-gaap	Interest And Dividend Income Securities InterestAndDividendIncomeSecurities	3565000	usd
CY2022	us-gaap	Interest And Dividend Income Securities InterestAndDividendIncomeSecurities	3268000	usd
CY2023	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-192600000	usd
CY2024	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	1270000000	usd
CY2024	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	14900000	usd
CY2024	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	1600000	usd
CY2024	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-13300000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Fee And Loan In Process FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcess	7923251000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Fee And Loan In Process FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcess	7984381000	usd
CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	23035000	usd
CY2023Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	23759000	usd
CY2024Q3	us-gaap	Financing Receivable Unamortized Loan Fee Cost FinancingReceivableUnamortizedLoanFeeCost	-30336000	usd
CY2023Q3	us-gaap	Financing Receivable Unamortized Loan Fee Cost FinancingReceivableUnamortizedLoanFeeCost	-31335000	usd
CY2024Q3	us-gaap	Financing Receivable Unamortized Purchase Premium Discount FinancingReceivableUnamortizedPurchasePremiumDiscount	37458000	usd
CY2023Q3	us-gaap	Financing Receivable Unamortized Purchase Premium Discount FinancingReceivableUnamortizedPurchasePremiumDiscount	41662000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	7907338000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	7970949000	usd
CY2024Q3	cffn	Aggregate Amount Of Loans Serviced For Others AggregateAmountOfLoansServicedForOthers	38100000	usd
CY2023Q3	cffn	Aggregate Amount Of Loans Serviced For Others AggregateAmountOfLoansServicedForOthers	44200000	usd
CY2024Q3	cffn	Escrow Balances Held On Loans Serviced For Others EscrowBalancesHeldOnLoansServicedForOthers	942000	usd
CY2023Q3	cffn	Escrow Balances Held On Loans Serviced For Others EscrowBalancesHeldOnLoansServicedForOthers	972000	usd
CY2024Q3	cffn	Loan To Value Ratio For Securing Commercial Real Estate Loans Maximum LoanToValueRatioForSecuringCommercialRealEstateLoansMaximum	0.85
CY2024Q3	cffn	Debt Service Coverage Ratio For Commercial Real Estate Loans Minimum DebtServiceCoverageRatioForCommercialRealEstateLoansMinimum	1.15
CY2024Q3	cffn	Loanto Value Ratiofor Securing Commercial Construction Loans Maximum LoantoValueRatioforSecuringCommercialConstructionLoansMaximum	0.80
CY2024Q3	cffn	Debt Service Coverage Ratio For Commercial Real Estate Loans Minimum DebtServiceCoverageRatioForCommercialRealEstateLoansMinimum	1.15
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year One Originated Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear	639789000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Two Originated Fiscal Year Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear	1096101000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Three Originated Two Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYear	1372917000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Four Originated Three Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYear	1529818000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Five Originated Four Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYear	827047000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Originated More Than Five Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYear	2339984000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Revolving FinancingReceivableExcludingAccruedInterestRevolving	118360000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Revolving Converted To Term Loan FinancingReceivableExcludingAccruedInterestRevolvingConvertedToTermLoan	6357000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	7930373000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year One Originated Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear	1124730000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Two Originated Fiscal Year Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear	1450679000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Three Originated Two Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYear	1709273000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Four Originated Three Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYear	904106000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Five Originated Four Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYear	403494000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Originated More Than Five Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYear	2285008000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Revolving FinancingReceivableExcludingAccruedInterestRevolving	110969000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Revolving Converted To Term Loan FinancingReceivableExcludingAccruedInterestRevolvingConvertedToTermLoan	6449000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	7994708000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year One Originated Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear	639789000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Two Originated Fiscal Year Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear	1096101000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Three Originated Two Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYear	1372917000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Four Originated Three Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYear	1529818000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Five Originated Four Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYear	827047000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Originated More Than Five Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYear	2339984000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Revolving FinancingReceivableExcludingAccruedInterestRevolving	118360000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Revolving Converted To Term Loan FinancingReceivableExcludingAccruedInterestRevolvingConvertedToTermLoan	6357000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	7930373000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year One Originated Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear	1124730000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Two Originated Fiscal Year Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear	1450679000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Three Originated Two Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYear	1709273000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Four Originated Three Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYear	904106000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Five Originated Four Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYear	403494000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Originated More Than Five Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYear	2285008000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Revolving FinancingReceivableExcludingAccruedInterestRevolving	110969000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Revolving Converted To Term Loan FinancingReceivableExcludingAccruedInterestRevolvingConvertedToTermLoan	6449000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	7994708000	usd
CY2024	us-gaap	Financing Receivable Excluding Accrued Interest Year One Originated Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYearWriteoff	96000	usd
CY2024	us-gaap	Financing Receivable Excluding Accrued Interest Year Two Originated Fiscal Year Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYearWriteoff	10000	usd
CY2024	us-gaap	Financing Receivable Excluding Accrued Interest Year Three Originated Two Years Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYearWriteoff	15000	usd
CY2024	us-gaap	Financing Receivable Excluding Accrued Interest Year Four Originated Three Years Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYearWriteoff	0	usd
CY2024	us-gaap	Financing Receivable Excluding Accrued Interest Year Five Originated Four Years Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYearWriteoff	0	usd
CY2024	us-gaap	Financing Receivable Excluding Accrued Interest Originated More Than Five Years Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearWriteoff	39000	usd
CY2024	us-gaap	Financing Receivable Excluding Accrued Interest Revolving Writeoff FinancingReceivableExcludingAccruedInterestRevolvingWriteoff	0	usd
CY2024	us-gaap	Financing Receivable Excluding Accrued Interest Revolving Converted To Term Loan Writeoff FinancingReceivableExcludingAccruedInterestRevolvingConvertedToTermLoanWriteoff	0	usd
CY2024	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Writeoff FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff	160000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	7930373000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	7994708000	usd
CY2024Q3	us-gaap	Mortgage Loans In Process Of Foreclosure Amount MortgageLoansInProcessOfForeclosureAmount	1600000	usd
CY2023Q3	us-gaap	Mortgage Loans In Process Of Foreclosure Amount MortgageLoansInProcessOfForeclosureAmount	2500000	usd
CY2024Q3	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	55000	usd
CY2023Q3	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	219000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Nonaccrual FinancingReceivableExcludingAccruedInterestNonaccrual	10166000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Nonaccrual No Allowance FinancingReceivableExcludingAccruedInterestNonaccrualNoAllowance	3010000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Nonaccrual FinancingReceivableExcludingAccruedInterestNonaccrual	9453000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Nonaccrual No Allowance FinancingReceivableExcludingAccruedInterestNonaccrualNoAllowance	1990000	usd
CY2024	us-gaap	Financing Receivable Excluding Accrued Interest Modified Period FinancingReceivableExcludingAccruedInterestModifiedPeriod	19735000	usd
CY2024	us-gaap	Financing Receivable Modification To Total Financing Receivables Excluding Accrued Interest Percent FinancingReceivableModificationToTotalFinancingReceivablesExcludingAccruedInterestPercent	0.0025
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Modified Past12 Months FinancingReceivableExcludingAccruedInterestModifiedPast12Months	19735000	usd
CY2023	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	4	contract
CY2023	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	669000	usd
CY2023	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	690000	usd
CY2022	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	6	contract
CY2022	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	299000	usd
CY2022	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	299000	usd
CY2023	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	1	contract
CY2023	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	8000	usd
CY2022	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	3	contract
CY2022	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	716000	usd
CY2023Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	23759000	usd
CY2024	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Writeoff FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff	160000	usd
CY2024	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Recovery FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossRecovery	49000	usd
CY2024	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	-633000	usd
CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	23035000	usd
CY2022Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	16371000	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Writeoff FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff	115000	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Recovery FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossRecovery	9000	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	7494000	usd
CY2023Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	23759000	usd
CY2021Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	19823000	usd
CY2022	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Writeoff FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff	70000	usd
CY2022	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Recovery FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossRecovery	256000	usd
CY2022	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	-3638000	usd
CY2022Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	16371000	usd
CY2024Q3	cffn	Off Balance Sheet Credit Exposures OffBalanceSheetCreditExposures	826500000	usd
CY2023Q3	cffn	Off Balance Sheet Credit Exposures OffBalanceSheetCreditExposures	837700000	usd
CY2023Q3	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	4095000	usd
CY2022Q3	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	4751000	usd
CY2024	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	1892000	usd
CY2023	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	-656000	usd
CY2024Q3	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	6003000	usd
CY2023Q3	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	4095000	usd
CY2024Q3	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	199285000	usd
CY2023Q3	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	192239000	usd
CY2024Q3	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	107822000	usd
CY2023Q3	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	100708000	usd
CY2024Q3	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	91463000	usd
CY2023Q3	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	91531000	usd
CY2024Q3	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	8500000	usd
CY2023Q3	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	11300000	usd
CY2024Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	8900000	usd
CY2023Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	11600000	usd
CY2024Q3	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P24Y1M6D
CY2024Q3	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0269
CY2024	us-gaap	Operating Lease Cost OperatingLeaseCost	1141000	usd
CY2023	us-gaap	Operating Lease Cost OperatingLeaseCost	1307000	usd
CY2022	us-gaap	Operating Lease Cost OperatingLeaseCost	1397000	usd
CY2024	us-gaap	Variable Lease Cost VariableLeaseCost	176000	usd
CY2023	us-gaap	Variable Lease Cost VariableLeaseCost	189000	usd
CY2022	us-gaap	Variable Lease Cost VariableLeaseCost	164000	usd
CY2024	us-gaap	Short Term Lease Cost ShortTermLeaseCost	2000	usd
CY2023	us-gaap	Short Term Lease Cost ShortTermLeaseCost	41000	usd
CY2022	us-gaap	Short Term Lease Cost ShortTermLeaseCost	2000	usd
CY2024	us-gaap	Operating Lease Payments OperatingLeasePayments	1130000	usd
CY2023	us-gaap	Operating Lease Payments OperatingLeasePayments	1211000	usd
CY2022	us-gaap	Operating Lease Payments OperatingLeasePayments	1312000	usd
CY2024Q3	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	1000000.0	usd
CY2024Q3	us-gaap	Finance Lease Liability FinanceLeaseLiability	1100000	usd
CY2024Q3	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P20Y
CY2024Q3	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.0517
CY2024	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	59000	usd
CY2024	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	53000	usd
CY2024	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	73000	usd
CY2024Q3	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	715000	usd
CY2024Q3	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	91000	usd
CY2024Q3	cffn	Lease Liability To Be Paid Year One LeaseLiabilityToBePaidYearOne	806000	usd
CY2024Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	648000	usd
CY2024Q3	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	91000	usd
CY2024Q3	cffn	Lease Liability To Be Paid Year Two LeaseLiabilityToBePaidYearTwo	739000	usd
CY2024Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	636000	usd
CY2024Q3	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	91000	usd
CY2024Q3	cffn	Lease Liability To Be Paid Year Three LeaseLiabilityToBePaidYearThree	727000	usd
CY2024Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	603000	usd
CY2024Q3	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	94000	usd
CY2024Q3	cffn	Lease Liability To Be Paid Year Four LeaseLiabilityToBePaidYearFour	697000	usd
CY2024Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	435000	usd
CY2024Q3	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	83000	usd
CY2024Q3	cffn	Lease Liability To Be Paid Year Five LeaseLiabilityToBePaidYearFive	518000	usd
CY2024Q3	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	9727000	usd
CY2024Q3	us-gaap	Finance Lease Liability Payments Due After Year Five FinanceLeaseLiabilityPaymentsDueAfterYearFive	1386000	usd
CY2024Q3	cffn	Lease Liability To Be Paid Thereafter LeaseLiabilityToBePaidThereafter	11113000	usd
CY2024Q3	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	12764000	usd
CY2024Q3	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	1836000	usd
CY2024Q3	cffn	Lease Liability To Be Paid LeaseLiabilityToBePaid	14600000	usd
CY2024Q3	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	3842000	usd
CY2024Q3	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	754000	usd
CY2024Q3	cffn	Lease Liability Amounts Representing Interest LeaseLiabilityAmountsRepresentingInterest	4596000	usd
CY2024Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	8922000	usd
CY2024Q3	us-gaap	Finance Lease Liability FinanceLeaseLiability	1082000	usd
CY2024Q3	cffn	Total Lease Liabilities TotalLeaseLiabilities	10004000	usd
CY2024Q3	cffn	Investment In Affordable Housing Limited Partnerships InvestmentInAffordableHousingLimitedPartnerships	131400000	usd
CY2023Q3	cffn	Investment In Affordable Housing Limited Partnerships InvestmentInAffordableHousingLimitedPartnerships	121800000	usd
CY2024Q3	us-gaap	Qualified Affordable Housing Project Investments Commitment QualifiedAffordableHousingProjectInvestmentsCommitment	74300000	usd
CY2023Q3	us-gaap	Qualified Affordable Housing Project Investments Commitment QualifiedAffordableHousingProjectInvestmentsCommitment	63600000	usd
CY2024	us-gaap	Affordable Housing Tax Credits Commitment Year To Be Paid AffordableHousingTaxCreditsCommitmentYearToBePaid	2027
CY2024	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	10400000	usd
CY2023	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	10100000	usd
CY2022	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	9300000	usd
CY2024	us-gaap	Affordable Housing Tax Credits And Other Tax Benefits Amount AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount	12600000	usd
CY2023	us-gaap	Affordable Housing Tax Credits And Other Tax Benefits Amount AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount	12400000	usd
CY2022	us-gaap	Affordable Housing Tax Credits And Other Tax Benefits Amount AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount	11600000	usd
CY2024	cffn	Net Income Tax Benefit Low Income Housing Partnerships NetIncomeTaxBenefitLowIncomeHousingPartnerships	2200000	usd
CY2023	cffn	Net Income Tax Benefit Low Income Housing Partnerships NetIncomeTaxBenefitLowIncomeHousingPartnerships	2300000	usd
CY2022	cffn	Net Income Tax Benefit Low Income Housing Partnerships NetIncomeTaxBenefitLowIncomeHousingPartnerships	2300000	usd
CY2024	us-gaap	Affordable Housing Project Investment Write Down Amount AffordableHousingProjectInvestmentWriteDownAmount	0	usd
CY2023	us-gaap	Affordable Housing Project Investment Write Down Amount AffordableHousingProjectInvestmentWriteDownAmount	0	usd
CY2022	us-gaap	Affordable Housing Project Investment Write Down Amount AffordableHousingProjectInvestmentWriteDownAmount	0	usd
CY2021Q3	us-gaap	Goodwill Goodwill	9324000	usd
CY2021Q3	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	3961000	usd
CY2022	cffn	Amortization Of Goodwill AmortizationOfGoodwill	0	usd
CY2022	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1372000	usd
CY2022Q3	us-gaap	Goodwill Goodwill	9324000	usd
CY2022Q3	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	2589000	usd
CY2023	cffn	Amortization Of Goodwill AmortizationOfGoodwill	0	usd
CY2023	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1069000	usd
CY2023Q3	us-gaap	Goodwill Goodwill	9324000	usd
CY2023Q3	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	1520000	usd
CY2024	cffn	Amortization Of Goodwill AmortizationOfGoodwill	0	usd
CY2024	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	774000	usd
CY2024Q3	us-gaap	Goodwill Goodwill	9324000	usd
CY2024Q3	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	746000	usd
CY2024Q3	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	0	usd
CY2024Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	523000	usd
CY2024Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	223000	usd
CY2024Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	0	usd
CY2024Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	0	usd
CY2024Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	0	usd
CY2024Q3	us-gaap	Noninterest Bearing Deposit Liabilities Domestic NoninterestBearingDepositLiabilitiesDomestic	549600000	usd
CY2023Q3	us-gaap	Noninterest Bearing Deposit Liabilities Domestic NoninterestBearingDepositLiabilitiesDomestic	558300000	usd
CY2024Q3	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	516300000	usd
CY2023Q3	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	521000000.0	usd
CY2024Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary By Interest Rate Type Fixed Rate FederalHomeLoanBankAdvancesMaturitiesSummaryByInterestRateTypeFixedRate	1980000000	usd
CY2024Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary By Interest Rate Type Floating Rate FederalHomeLoanBankAdvancesMaturitiesSummaryByInterestRateTypeFloatingRate	200000000.0	usd
CY2024Q3	us-gaap	Finance Lease Liability FinanceLeaseLiability	1100000	usd
CY2023Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary By Interest Rate Type Fixed Rate FederalHomeLoanBankAdvancesMaturitiesSummaryByInterestRateTypeFixedRate	2020000000.00	usd
CY2023Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary By Interest Rate Type Floating Rate FederalHomeLoanBankAdvancesMaturitiesSummaryByInterestRateTypeFloatingRate	365000000.0	usd
CY2024Q3	us-gaap	Line Of Credit LineOfCredit	0	usd
CY2023Q3	us-gaap	Line Of Credit LineOfCredit	0	usd
CY2024Q3	us-gaap	Advances From Federal Home Loan Banks AdvancesFromFederalHomeLoanBanks	2180656000	usd
CY2023Q3	us-gaap	Advances From Federal Home Loan Banks AdvancesFromFederalHomeLoanBanks	2382828000	usd
CY2024Q3	cffn	Prepayment Penalty On Fhlb Advances PrepaymentPenaltyOnFhlbAdvances	2173000	usd
CY2023Q3	cffn	Prepayment Penalty On Fhlb Advances PrepaymentPenaltyOnFhlbAdvances	3703000	usd
CY2023Q3	us-gaap	Debt Longterm And Shortterm Combined Amount DebtLongtermAndShorttermCombinedAmount	2879125000	usd
CY2024Q3	cffn	Fhlb Borrowings Threshold Percentage Of Regulatory Assets FHLBBorrowingsThresholdPercentageOfRegulatoryAssets	0.40
CY2024Q3	cffn	Fhl Bborrowingsthresholdpercentageofregulatoryassetstemporaryincrease FHLBborrowingsthresholdpercentageofregulatoryassetstemporaryincrease	0.50
CY2024Q3	cffn	Fhlb Percentage Of Regulatory Assets FhlbPercentageOfRegulatoryAssets	0.23
CY2024Q3	us-gaap	Derivative Asset Notional Amount DerivativeAssetNotionalAmount	200000000.0	usd
CY2023Q3	us-gaap	Derivative Asset Notional Amount DerivativeAssetNotionalAmount	365000000.0	usd
CY2024Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary By Interest Rate Type Floating Rate FederalHomeLoanBankAdvancesMaturitiesSummaryByInterestRateTypeFloatingRate	200000000.0	usd
CY2023Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary By Interest Rate Type Floating Rate FederalHomeLoanBankAdvancesMaturitiesSummaryByInterestRateTypeFloatingRate	365000000.0	usd
CY2024	us-gaap	Derivative Average Remaining Maturity1 DerivativeAverageRemainingMaturity1	P2Y3M18D
CY2023	us-gaap	Derivative Average Remaining Maturity1 DerivativeAverageRemainingMaturity1	P2Y1M6D
CY2024Q3	us-gaap	Derivative Fair Value Of Derivative Net DerivativeFairValueOfDerivativeNet	2100000	usd
CY2023Q3	us-gaap	Derivative Fair Value Of Derivative Net DerivativeFairValueOfDerivativeNet	13000000.0	usd
CY2024	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	6100000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	5600000	usd
CY2024	us-gaap	Derivative Instruments Gain Loss Reclassification From Accumulated Oci To Income Estimated Net Amount To Be Transferred DerivativeInstrumentsGainLossReclassificationFromAccumulatedOCIToIncomeEstimatedNetAmountToBeTransferred	-1800000	usd
CY2024Q3	us-gaap	Derivative Asset Fair Value Of Collateral DerivativeAssetFairValueOfCollateral	2100000	usd
CY2023Q3	us-gaap	Derivative Asset Fair Value Of Collateral DerivativeAssetFairValueOfCollateral	14000000.0	usd
CY2024Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due Within One Year Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueWithinOneYearOfBalanceSheetDate	650000000	usd
CY2024Q3	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	2204587000	usd
CY2024Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due From One To Two Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromOneToTwoYearsOfBalanceSheetDate	575000000	usd
CY2024Q3	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	515572000	usd
CY2024Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due From Two To Three Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromTwoToThreeYearsOfBalanceSheetDate	477500000	usd
CY2024Q3	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	138893000	usd
CY2024Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due From Three To Four Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromThreeToFourYearsOfBalanceSheetDate	310656000	usd
CY2024Q3	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	94600000	usd
CY2024Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due From Four To Five Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromFourToFiveYearsOfBalanceSheetDate	167500000	usd
CY2024Q3	us-gaap	Time Deposit Maturities Year Five TimeDepositMaturitiesYearFive	11455000	usd
CY2024Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due After Five Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueAfterFiveYearsOfBalanceSheetDate	0	usd
CY2024Q3	us-gaap	Time Deposit Maturities After Year Five TimeDepositMaturitiesAfterYearFive	203000	usd
CY2024Q3	us-gaap	Advances From Federal Home Loan Banks AdvancesFromFederalHomeLoanBanks	2180656000	usd
CY2024Q3	us-gaap	Interest Bearing Domestic Deposit Certificates Of Deposits InterestBearingDomesticDepositCertificatesOfDeposits	2965310000	usd
CY2024	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	12153000	usd
CY2023	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	6789000	usd
CY2022	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	17105000	usd
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CY2023	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	1435000	usd
CY2022	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	3598000	usd
CY2024	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	12547000	usd
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CY2022	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	20703000	usd
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CY2022	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	1632000	usd
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CY2023	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-6311000	usd
CY2022	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	415000	usd
CY2024	us-gaap	Deferred Federal State And Local Tax Expense Benefit DeferredFederalStateAndLocalTaxExpenseBenefit	3546000	usd
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CY2022	us-gaap	Deferred Federal State And Local Tax Expense Benefit DeferredFederalStateAndLocalTaxExpenseBenefit	2047000	usd
CY2024	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	16093000	usd
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-37296000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	22750000	usd
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CY2024	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	11362000	usd
CY2024	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2023	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	-29180000	usd
CY2023	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2022	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	22513000	usd
CY2022	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
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CY2024	cffn	Income Tax Expense Related To The Banks Earning Distributions Percentage IncomeTaxExpenseRelatedToTheBanksEarningDistributionsPercentage	0.100
CY2023	cffn	Income Tax Expense Related To Banks Earning Distributions IncomeTaxExpenseRelatedToBanksEarningDistributions	0	usd
CY2023	cffn	Income Tax Expense Related To The Banks Earning Distributions Percentage IncomeTaxExpenseRelatedToTheBanksEarningDistributionsPercentage	0
CY2022	cffn	Income Tax Expense Related To Banks Earning Distributions IncomeTaxExpenseRelatedToBanksEarningDistributions	0	usd
CY2022	cffn	Income Tax Expense Related To The Banks Earning Distributions Percentage IncomeTaxExpenseRelatedToTheBanksEarningDistributionsPercentage	0
CY2024	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	2497000	usd
CY2024	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.048
CY2023	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	-5412000	usd
CY2023	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.039
CY2022	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	3399000	usd
CY2022	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.032
CY2024	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	2244000	usd
CY2024	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.042
CY2023	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	2303000	usd
CY2023	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	-0.016
CY2022	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	2238000	usd
CY2022	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.021
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CY2024	cffn	Effective Income Tax Rate Esop Related Expenses Net EffectiveIncomeTaxRateEsopRelatedExpensesNet	-0.008
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CY2023	cffn	Effective Income Tax Rate Esop Related Expenses Net EffectiveIncomeTaxRateEsopRelatedExpensesNet	0.005
CY2022	cffn	Esop Related Expenses Net EsopRelatedExpensesNet	-641000	usd
CY2022	cffn	Effective Income Tax Rate Esop Related Expenses Net EffectiveIncomeTaxRateEsopRelatedExpensesNet	-0.006
CY2024	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-480000	usd
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CY2023	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	251000	usd
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CY2022	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-283000	usd
CY2022	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.003
CY2024	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	16093000	usd
CY2024	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.297
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-37296000	usd
CY2023	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.268
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	22750000	usd
CY2022	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.212
CY2024	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21
CY2024	cffn	Income Tax Expense Related To Banks Earning Distributions IncomeTaxExpenseRelatedToBanksEarningDistributions	5400000	usd
CY2024Q3	us-gaap	Bad Debt Reserve For Tax Purposes Of Qualified Lender BadDebtReserveForTaxPurposesOfQualifiedLender	75900000	usd
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CY2023Q3	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	0	usd
CY2024Q3	us-gaap	Deferred Tax Assets Tax Credit Carryforwards DeferredTaxAssetsTaxCreditCarryforwards	12813000	usd
CY2023Q3	us-gaap	Deferred Tax Assets Tax Credit Carryforwards DeferredTaxAssetsTaxCreditCarryforwards	0	usd
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CY2023Q3	us-gaap	Deferred Tax Assets Unrealized Losses On Availablefor Sale Securities Gross DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross	368000	usd
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CY2023Q3	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	2748000	usd
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CY2023Q3	us-gaap	Deferred Tax Liabilities Derivatives DeferredTaxLiabilitiesDerivatives	3176000	usd
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CY2024Q3	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	553000	usd
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CY2024Q3	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	33615000	usd
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CY2023	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	356000	usd
CY2022	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-159770000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	25339000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax	1647000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	-5103000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-159770000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	30442000	usd
CY2024	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	15300000	usd
CY2023	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	17600000	usd
CY2022	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	18100000	usd
CY2024	cffn	Interchange Network Charges InterchangeNetworkCharges	4200000	usd
CY2023	cffn	Interchange Network Charges InterchangeNetworkCharges	4000000.0	usd
CY2022	cffn	Interchange Network Charges InterchangeNetworkCharges	3600000	usd
CY2024	dei	Auditor Name AuditorName	KPMG LLP
CY2024	dei	Auditor Location AuditorLocation	Kansas City, Missouri
CY2024	dei	Auditor Firm AuditorFirmId	185
CY2024	ecd	Rule10b51 Arr Trmntd Flag Rule10b51ArrTrmntdFlag	false
CY2024	ecd	Non Rule10b51 Arr Trmntd Flag NonRule10b51ArrTrmntdFlag	false
CY2024	ecd	Non Rule10b51 Arr Adopted Flag NonRule10b51ArrAdoptedFlag	false
CY2024	ecd	Rule10b51 Arr Adopted Flag Rule10b51ArrAdoptedFlag	false

Files In Submission

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0001490906-24-000035-index.html	Edgar Link	pending
0001490906-24-000035.txt	Edgar Link	pending
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cffn-20240930_g1.jpg	Edgar Link	pending
Financial_Report.xlsx	Edgar Link	pending
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cffn-20240930_def.xml	Edgar Link	unprocessable
cffn-20240930_pre.xml	Edgar Link	unprocessable

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$CFFN
Capitol Federal Financial, Inc. Stock $cffn

2024 Q4 Form 10-K Financial Statement

#000149090624000035 Filed on November 27, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CFFN Capitol Federal Financial, Inc. Stock $cffn

2024 Q4 Form 10-K Financial Statement

#000149090624000035 Filed on November 27, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CFFN
Capitol Federal Financial, Inc. Stock $cffn