$CFFN
Capitol Federal Financial, Inc. Stock $cffn

$cffn Overview Financials Valuation SEC Filings Company Website

2021 Q3 Form 10-K Financial Statement

#000149090621000065 Filed on November 24, 2021

Income Statement

Concept	2021 Q3	2021	2020 Q3
Revenue		$258.2M	$71.61M
YoY Change		-15.34%	-14.02%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development		$17.92M
YoY Change		5.59%
% of Gross Profit
Depreciation & Amortization	$2.800M	$11.00M	$2.800M
YoY Change	0.0%	-0.9%	3.7%
% of Gross Profit
Operating Expenses		$17.92M
YoY Change		5.59%
Operating Profit
YoY Change
Interest Expense		$83.18M
YoY Change		-28.07%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$23.92M	$96.03M	$23.49M
YoY Change	1.83%	19.1%	-19.11%
Income Tax	$5.370M	$19.95M	$5.210M
% Of Pretax Income	22.45%	20.77%	22.18%
Net Earnings	$18.55M	$76.08M	$18.28M
YoY Change	1.48%	17.88%	-18.43%
Net Earnings / Revenue		29.47%	25.53%
Basic Earnings Per Share		$0.56	$0.13
Diluted Earnings Per Share	$136.8K	$0.56	$0.13
COMMON SHARES
Basic Shares Outstanding	138.8M shares	135.5M shares	137.7M shares
Diluted Shares Outstanding		135.5M shares	137.7M shares

Balance Sheet

Concept	2021 Q3	2021	2020 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$42.30M		$185.1M
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	$99.13M	$111.8M	$101.9M
YoY Change	-2.7%	-4.12%	5.26%
Goodwill	$9.324M
YoY Change
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets
YoY Change
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$9.631B	$9.631B	$9.487B
YoY Change	1.52%	1.52%	1.58%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$129.0M	$129.3M	$132.0M
YoY Change	-2.27%	-2.19%	29.41%
Accrued Expenses	$13.00M	$12.80M	$15.00M
YoY Change	-13.33%	-12.93%
Deferred Revenue
YoY Change
Short-Term Debt
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$143.0M	$143.0M	$148.0M
YoY Change	-3.38%	-3.18%	45.1%
LONG-TERM LIABILITIES
Long-Term Debt	$0.00	$0.00	$0.00
YoY Change
Other Long-Term Liabilities	$73.00M	$72.70M	$66.00M
YoY Change	10.61%	10.65%	0.0%
Total Long-Term Liabilities	$73.00M	$72.70M	$66.00M
YoY Change	10.61%	10.65%	0.0%
TOTAL LIABILITIES
Total Short-Term Liabilities	$143.0M	$143.0M	$148.0M
Total Long-Term Liabilities	$73.00M	$72.70M	$66.00M
Total Liabilities	$8.389B	$8.402B	$8.202B
YoY Change	2.28%	2.43%	2.48%
SHAREHOLDERS EQUITY
Retained Earnings	$98.94M		$143.2M
YoY Change	-30.89%		-17.85%
Common Stock	$1.191B		$1.191B
YoY Change	-0.02%		-1.68%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$1.242B	$1.230B	$1.285B
YoY Change
Total Liabilities & Shareholders Equity	$9.631B	$9.631B	$9.487B
YoY Change	1.52%	1.52%	1.58%

Cashflow Statement

Concept	2021 Q3	2021	2020 Q3
OPERATING ACTIVITIES
Net Income	$18.55M	$76.08M	$18.28M
YoY Change	1.48%	17.88%	-18.43%
Depreciation, Depletion And Amortization	$2.800M	$11.00M	$2.800M
YoY Change	0.0%	-0.9%	3.7%
Cash From Operating Activities	$23.10M	$74.47M	$23.80M
YoY Change	-2.94%	-19.87%	-6.3%
INVESTING ACTIVITIES
Capital Expenditures	-$1.300M	$9.410M	-$5.300M
YoY Change	-75.47%	-36.17%	82.76%
Acquisitions
YoY Change
Other Investing Activities	-$51.00M	-$317.3M	-$148.8M
YoY Change	-65.73%	132.45%	-202.13%
Cash From Investing Activities	-$52.30M	-$326.7M	-$154.1M
YoY Change	-66.06%	115.92%	-207.84%
FINANCING ACTIVITIES
Cash Dividend Paid		$117.9M
YoY Change		25.6%
Common Stock Issuance & Retirement, Net		$4.568M
YoY Change		-78.0%
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-27.00M	$82.79M	-84.10M
YoY Change	-67.9%	86.58%	-649.67%
NET CHANGE
Cash From Operating Activities	23.10M	$74.47M	23.80M
Cash From Investing Activities	-52.30M	-$326.7M	-154.1M
Cash From Financing Activities	-27.00M	$82.79M	-84.10M
Net Change In Cash	-56.20M	-$169.4M	-214.4M
YoY Change	-73.79%	1110.81%	-216.78%
FREE CASH FLOW
Cash From Operating Activities	$23.10M	$74.47M	$23.80M
Capital Expenditures	-$1.300M	$9.410M	-$5.300M
Free Cash Flow	$24.40M	$65.06M	$29.10M
YoY Change	-16.15%	-16.79%	2.83%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2021	dei	Document Type DocumentType	10-K
CY2021	dei	Document Annual Report DocumentAnnualReport	true
CY2021	dei	Document Period End Date DocumentPeriodEndDate	2021-09-30
CY2021	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--09-30
CY2021	dei	Document Transition Report DocumentTransitionReport	false
CY2021	dei	Entity File Number EntityFileNumber	001-34814
CY2021	dei	Entity Registrant Name EntityRegistrantName	Capitol Federal Financial, Inc.
CY2021	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	MD
CY2021	dei	City Area Code CityAreaCode	785
CY2021	dei	Entity Address Address Line1 EntityAddressAddressLine1	700 South Kansas Avenue,
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CY2021	dei	Security12b Title Security12bTitle	Common Stock, par value $0.01 per share
CY2021	dei	Trading Symbol TradingSymbol	CFFN
CY2021	dei	Security Exchange Name SecurityExchangeName	NASDAQ
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CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	16090000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	26411000	USD
CY2021	us-gaap	Net Income Loss NetIncomeLoss	76082000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	64540000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	94243000	USD
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.56
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.47
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.68
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.56
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.47
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.68
CY2021	us-gaap	Net Income Loss NetIncomeLoss	76082000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	64540000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	94243000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	-6116000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	4359000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	3468000	USD
CY2021	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-19077000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	13578000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	10804000	USD
CY2021	us-gaap	Other Comprehensive Income Reclassification Adjustment For Held To Maturity Transferred To Available For Sale Securities Tax OtherComprehensiveIncomeReclassificationAdjustmentForHeldToMaturityTransferredToAvailableForSaleSecuritiesTax	0	USD
CY2020	us-gaap	Other Comprehensive Income Reclassification Adjustment For Held To Maturity Transferred To Available For Sale Securities Tax OtherComprehensiveIncomeReclassificationAdjustmentForHeldToMaturityTransferredToAvailableForSaleSecuritiesTax	0	USD
CY2019	us-gaap	Other Comprehensive Income Reclassification Adjustment For Held To Maturity Transferred To Available For Sale Securities Tax OtherComprehensiveIncomeReclassificationAdjustmentForHeldToMaturityTransferredToAvailableForSaleSecuritiesTax	750000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Transfers From Held To Maturity To Available For Sale Securities Net Of Tax OtherComprehensiveIncomeLossTransfersFromHeldToMaturityToAvailableForSaleSecuritiesNetOfTax	0	USD
CY2020	us-gaap	Other Comprehensive Income Loss Transfers From Held To Maturity To Available For Sale Securities Net Of Tax OtherComprehensiveIncomeLossTransfersFromHeldToMaturityToAvailableForSaleSecuritiesNetOfTax	0	USD
CY2019	us-gaap	Other Comprehensive Income Loss Transfers From Held To Maturity To Available For Sale Securities Net Of Tax OtherComprehensiveIncomeLossTransfersFromHeldToMaturityToAvailableForSaleSecuritiesNetOfTax	2336000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax	6153000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax	-4875000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax	-10394000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	19277000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-15184000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-32379000	USD
CY2021	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	76282000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	62934000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	75004000	USD
CY2018Q3	us-gaap	Stockholders Equity StockholdersEquity	1391622000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	94243000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-19239000	USD
CY2019	us-gaap	Stock Issued During Period Value Employee Stock Ownership Plan StockIssuedDuringPeriodValueEmployeeStockOwnershipPlan	2200000	USD
CY2019	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	-2000	USD
CY2019	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	552000	USD
CY2019	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	1485000	USD
CY2019	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.98
CY2019	us-gaap	Dividends Cash DividendsCash	134929000	USD
CY2019Q3	us-gaap	Stockholders Equity StockholdersEquity	1336326000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	64540000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-1606000	USD
CY2020	us-gaap	Stock Issued During Period Value Employee Stock Ownership Plan StockIssuedDuringPeriodValueEmployeeStockOwnershipPlan	1988000	USD
CY2020	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	-19000	USD
CY2020	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	570000	USD
CY2020	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	23804000	USD
CY2020	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	638000	USD
CY2020	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.68
CY2020	us-gaap	Dividends Cash DividendsCash	93862000	USD
CY2020Q3	us-gaap	Stockholders Equity StockholdersEquity	1284859000	USD
CY2021	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	-8510000	USD
CY2021	us-gaap	Net Income Loss NetIncomeLoss	76082000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	200000	USD
CY2021	us-gaap	Stock Issued During Period Value Employee Stock Ownership Plan StockIssuedDuringPeriodValueEmployeeStockOwnershipPlan	2036000	USD
CY2021	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	-16000	USD
CY2021	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	496000	USD
CY2021	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	1530000	USD
CY2021	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	324000	USD
CY2021	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.87
CY2021	us-gaap	Dividends Cash DividendsCash	117890000	USD
CY2021Q3	us-gaap	Stockholders Equity StockholdersEquity	1242273000	USD
CY2021	us-gaap	Net Income Loss NetIncomeLoss	76082000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	64540000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	94243000	USD
CY2021	us-gaap	Dividend Income Operating DividendIncomeOperating	3916000	USD
CY2020	us-gaap	Dividend Income Operating DividendIncomeOperating	5827000	USD
CY2019	us-gaap	Dividend Income Operating DividendIncomeOperating	7823000	USD
CY2020	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	22300000	USD
CY2019	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	750000	USD
CY2021	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	1780000	USD
CY2020	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	0	USD
CY2019	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	0	USD
CY2021	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	1825000	USD
CY2020	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	0	USD
CY2019	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	0	USD
CY2021	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-6206000	USD
CY2020	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-1661000	USD
CY2019	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-1242000	USD
CY2021	us-gaap	Depreciation Nonproduction DepreciationNonproduction	9372000	USD
CY2020	us-gaap	Depreciation Nonproduction DepreciationNonproduction	9133000	USD
CY2019	us-gaap	Depreciation Nonproduction DepreciationNonproduction	9143000	USD
CY2021	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1578000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1964000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	2316000	USD
CY2021	cffn	Amortization Of Deferred Amounts Related To Fhlb Advances Net AmortizationOfDeferredAmountsRelatedToFhlbAdvancesNet	1582000	USD
CY2020	cffn	Amortization Of Deferred Amounts Related To Fhlb Advances Net AmortizationOfDeferredAmountsRelatedToFhlbAdvancesNet	539000	USD
CY2019	cffn	Amortization Of Deferred Amounts Related To Fhlb Advances Net AmortizationOfDeferredAmountsRelatedToFhlbAdvancesNet	8000	USD
CY2021	us-gaap	Employee Stock Ownership Plan Esop Compensation Expense EmployeeStockOwnershipPlanESOPCompensationExpense	2036000	USD
CY2020	us-gaap	Employee Stock Ownership Plan Esop Compensation Expense EmployeeStockOwnershipPlanESOPCompensationExpense	1988000	USD
CY2019	us-gaap	Employee Stock Ownership Plan Esop Compensation Expense EmployeeStockOwnershipPlanESOPCompensationExpense	2200000	USD
CY2021	us-gaap	Share Based Compensation ShareBasedCompensation	496000	USD
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	570000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	552000	USD
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-1668000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-5588000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-361000	USD
CY2021	us-gaap	Equity Securities Fv Ni Realized Gain EquitySecuritiesFvNiRealizedGain	7386000	USD
CY2020	us-gaap	Equity Securities Fv Ni Realized Gain EquitySecuritiesFvNiRealizedGain	0	USD
CY2019	us-gaap	Equity Securities Fv Ni Realized Gain EquitySecuritiesFvNiRealizedGain	0	USD
CY2021	us-gaap	Increase Decrease Cash Collateral From Counterparties IncreaseDecreaseCashCollateralFromCounterparties	0	USD
CY2020	us-gaap	Increase Decrease Cash Collateral From Counterparties IncreaseDecreaseCashCollateralFromCounterparties	0	USD
CY2019	us-gaap	Increase Decrease Cash Collateral From Counterparties IncreaseDecreaseCashCollateralFromCounterparties	-9970000	USD
CY2021	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-12751000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-9105000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-6220000	USD
CY2021	us-gaap	Increase Decrease In Income Taxes Payable Net Of Income Taxes Receivable IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable	105000	USD
CY2020	us-gaap	Increase Decrease In Income Taxes Payable Net Of Income Taxes Receivable IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable	774000	USD
CY2019	us-gaap	Increase Decrease In Income Taxes Payable Net Of Income Taxes Receivable IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable	2173000	USD
CY2021	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-14306000	USD
CY2020	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-8231000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-19746000	USD
CY2021	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	74467000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	92928000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	80947000	USD
CY2021	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	1079351000	USD
CY2020	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	1007763000	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	386702000	USD
CY2021	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	594294000	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	667952000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	359551000	USD
CY2021	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	0	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	0	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	165336000	USD
CY2021	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	25386000	USD
CY2020	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	10421000	USD
CY2019	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	197054000	USD
CY2021	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	1029000	USD
CY2020	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	0	USD
CY2019	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	187961000	USD
CY2021	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	-132800000	USD
CY2020	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	-191359000	USD
CY2019	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	-95358000	USD
CY2021	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	9410000	USD
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	14742000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	11732000	USD
CY2021	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	194000	USD
CY2020	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	993000	USD
CY2019	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	2053000	USD
CY2021	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	0	USD
CY2020	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	0	USD
CY2019	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	302000	USD
CY2021	us-gaap	Proceeds From Sale Of Equity Securities Fv Ni ProceedsFromSaleOfEquitySecuritiesFvNi	7386000	USD
CY2020	us-gaap	Proceeds From Sale Of Equity Securities Fv Ni ProceedsFromSaleOfEquitySecuritiesFvNi	0	USD
CY2019	us-gaap	Proceeds From Sale Of Equity Securities Fv Ni ProceedsFromSaleOfEquitySecuritiesFvNi	0	USD
CY2021	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	2619000	USD
CY2020	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	0	USD
CY2019	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	0	USD
CY2021	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	443000	USD
CY2020	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	490000	USD
CY2019	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	0	USD
CY2021	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-326668000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-151290000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	233259000	USD
CY2021	us-gaap	Payments Of Dividends PaymentsOfDividends	117890000	USD
CY2020	us-gaap	Payments Of Dividends PaymentsOfDividends	93862000	USD
CY2019	us-gaap	Payments Of Dividends PaymentsOfDividends	134929000	USD
CY2021	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	405988000	USD
CY2020	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	609541000	USD
CY2019	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	-21487000	USD
CY2021	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	1143800000	USD
CY2020	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	1665600000	USD
CY2019	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	5518700000	USD
CY2021	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	1346800000	USD
CY2020	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	2112600000	USD
CY2019	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	5563752000	USD
CY2021	us-gaap	Increase Decrease In Advance Payments By Borrowers For Taxes And Insurance IncreaseDecreaseInAdvancePaymentsByBorrowersForTaxesAndInsurance	7008000	USD
CY2020	us-gaap	Increase Decrease In Advance Payments By Borrowers For Taxes And Insurance IncreaseDecreaseInAdvancePaymentsByBorrowersForTaxesAndInsurance	35000	USD
CY2019	us-gaap	Increase Decrease In Advance Payments By Borrowers For Taxes And Insurance IncreaseDecreaseInAdvancePaymentsByBorrowersForTaxesAndInsurance	422000	USD
CY2021	us-gaap	Payments Of Debt Restructuring Costs PaymentsOfDebtRestructuringCosts	5077000	USD
CY2020	us-gaap	Payments Of Debt Restructuring Costs PaymentsOfDebtRestructuringCosts	4215000	USD
CY2019	us-gaap	Payments Of Debt Restructuring Costs PaymentsOfDebtRestructuringCosts	0	USD
CY2021	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	4568000	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	20767000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	USD
CY2021	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	324000	USD
CY2020	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	638000	USD
CY2019	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	1485000	USD
CY2021	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	82785000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	44370000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-199561000	USD
CY2021	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-169416000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-13992000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	114645000	USD
CY2020Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	239708000	USD
CY2019Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	253700000	USD
CY2018Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	139055000	USD
CY2021Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	70292000	USD
CY2020Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	239708000	USD
CY2019Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	253700000	USD
CY2021	us-gaap	Income Taxes Paid IncomeTaxesPaid	13057000	USD
CY2020	us-gaap	Income Taxes Paid IncomeTaxesPaid	13045000	USD
CY2019	us-gaap	Income Taxes Paid IncomeTaxesPaid	17779000	USD
CY2021	us-gaap	Interest Paid Net InterestPaidNet	83646000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	118610000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	123508000	USD
CY2021	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	0	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	16841000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	0	USD
CY2021	cffn	Operating Lease Liability Obtained OperatingLeaseLiabilityObtained	0	USD
CY2020	cffn	Operating Lease Liability Obtained OperatingLeaseLiabilityObtained	16726000	USD
CY2019	cffn	Operating Lease Liability Obtained OperatingLeaseLiabilityObtained	0	USD
CY2021	us-gaap	Debt Securities Held To Maturity Transfer Amount DebtSecuritiesHeldToMaturityTransferAmount	0	USD
CY2020	us-gaap	Debt Securities Held To Maturity Transfer Amount DebtSecuritiesHeldToMaturityTransferAmount	0	USD
CY2019	us-gaap	Debt Securities Held To Maturity Transfer Amount DebtSecuritiesHeldToMaturityTransferAmount	444732000	USD
CY2021	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 45 traditional and nine 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 and purchasing one- to four-family loans, and providing personal retail financial services, along with offering commercial banking and lending products. The Bank is subject to competition from other financial institutions and other companies that provide financial services.
CY2021Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	42300000	USD
CY2020Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	185100000	USD
CY2021Q3	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	28000000	USD
CY2020Q3	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	54600000	USD
CY2021Q3	cffn	Interest Bearing Deposits Held At Federal Reserve Bank InterestBearingDepositsHeldAtFederalReserveBank	24100000	USD
CY2020Q3	cffn	Interest Bearing Deposits Held At Federal Reserve Bank InterestBearingDepositsHeldAtFederalReserveBank	172200000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0	USD
CY2021	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, the effective portion of 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. The ineffective portion of the change in fair value of the interest rate swap is recognized directly in 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.
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	31527000	USD
CY2020Q3	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	0	USD
CY2020Q3	cffn	Acl And Reserve For Off Balance Sheet Credit Exposures ACLAndReserveForOffBalanceSheetCreditExposures	31527000	USD
CY2021Q3	us-gaap	Financing Receivable Accrued Interest After Allowance For Credit Loss FinancingReceivableAccruedInterestAfterAllowanceForCreditLoss	18700000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Accrued Interest After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLoss	2900000	USD
CY2021	us-gaap	Net Income Loss NetIncomeLoss	76082000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	64540000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	94243000	USD
CY2021	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	50000	USD
CY2020	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	52000	USD
CY2019	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	55000	USD
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	76032000	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	64488000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	94188000	USD
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	135481232	shares
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	137896704	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	137676923	shares
CY2021	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	14363	shares
CY2020	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	4484	shares
CY2019	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	58478	shares
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	135495595	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	137901188	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	137735401	shares
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.56
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.47
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.68
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.56
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.47
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.68
CY2021	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	206284	shares
CY2020	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	437731	shares
CY2019	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	470938	shares
CY2021Q3	us-gaap	Debt Securities Available For Sale Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss	2008456000	USD
CY2021Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	18705000	USD
CY2021Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	12553000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest DebtSecuritiesAvailableForSaleExcludingAccruedInterest	2014608000	USD
CY2020Q3	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	1529605000	USD
CY2020Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	31717000	USD
CY2020Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	372000	USD
CY2020Q3	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	1560950000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	1398300000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	12488000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	10612000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	65000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	282030000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	371000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	118000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	1000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss	2008456000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest DebtSecuritiesAvailableForSaleExcludingAccruedInterest	2014608000	USD
CY2021	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	2710000	USD
CY2020	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	4242000	USD
CY2019	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	6020000	USD
CY2021	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	115000	USD
CY2020	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	225000	USD
CY2019	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	346000	USD
CY2021	us-gaap	Interest And Dividend Income Securities InterestAndDividendIncomeSecurities	2825000	USD
CY2020	us-gaap	Interest And Dividend Income Securities InterestAndDividendIncomeSecurities	4467000	USD
CY2019	us-gaap	Interest And Dividend Income Securities InterestAndDividendIncomeSecurities	6366000	USD
CY2021Q3	cffn	Pledged Financial Instruments Not Separately Reported Securitiesfor Public Unit Deposits PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesforPublicUnitDeposits	264885000	USD
CY2020Q3	cffn	Pledged Financial Instruments Not Separately Reported Securitiesfor Public Unit Deposits PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesforPublicUnitDeposits	330986000	USD
CY2021Q3	us-gaap	Pledged Financial Instruments Not Separately Reported Securities For Other Debt Facilities PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesForOtherDebtFacilities	64707000	USD
CY2020Q3	us-gaap	Pledged Financial Instruments Not Separately Reported Securities For Other Debt Facilities PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesForOtherDebtFacilities	259851000	USD
CY2021Q3	cffn	Pledged Financial Instruments Not Separately Reported Securities For Commercial Deposits PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesForCommercialDeposits	66256000	USD
CY2020Q3	cffn	Pledged Financial Instruments Not Separately Reported Securities For Commercial Deposits PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesForCommercialDeposits	0	USD
CY2021Q3	us-gaap	Pledged Financial Instruments Not Separately Reported Securities Pledged PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesPledged	395848000	USD
CY2020Q3	us-gaap	Pledged Financial Instruments Not Separately Reported Securities Pledged PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesPledged	590837000	USD
CY2021	us-gaap	Equity Securities Fv Ni Realized Gain EquitySecuritiesFvNiRealizedGain	7400000	USD
CY2021	us-gaap	Proceeds From Sale Of Equity Securities Fv Ni ProceedsFromSaleOfEquitySecuritiesFvNi	7400000	USD
CY2021Q3	us-gaap	Loans And Leases Receivable Before Fees Gross LoansAndLeasesReceivableBeforeFeesGross	7096073000	USD
CY2020Q3	us-gaap	Loans And Leases Receivable Before Fees Gross LoansAndLeasesReceivableBeforeFeesGross	7224996000	USD
CY2021Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	19823000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	31527000	USD
CY2021Q3	us-gaap	Loans And Leases Receivable Deferred Income LoansAndLeasesReceivableDeferredIncome	29556000	USD
CY2020Q3	us-gaap	Loans And Leases Receivable Deferred Income LoansAndLeasesReceivableDeferredIncome	29190000	USD
CY2021Q3	cffn	Loans And Leases Receivable Premiums Deferred Costs LoansAndLeasesReceivablePremiumsDeferredCosts	34448000	USD
CY2020Q3	cffn	Loans And Leases Receivable Premiums Deferred Costs LoansAndLeasesReceivablePremiumsDeferredCosts	38572000	USD
CY2021Q3	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	7081142000	USD
CY2020Q3	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	7202851000	USD
CY2021Q3	cffn	Aggregate Amount Of Loans Serviced For Others AggregateAmountOfLoansServicedForOthers	63400000	USD
CY2020Q3	cffn	Aggregate Amount Of Loans Serviced For Others AggregateAmountOfLoansServicedForOthers	87200000	USD
CY2021Q3	cffn	Escrow Balances Held On Loans Serviced For Others EscrowBalancesHeldOnLoansServicedForOthers	1400000	USD
CY2020Q3	cffn	Escrow Balances Held On Loans Serviced For Others EscrowBalancesHeldOnLoansServicedForOthers	1700000	USD
CY2021Q3	cffn	Loan To Value Ratio For Securing Commercial Real Estate Loans Maximum LoanToValueRatioForSecuringCommercialRealEstateLoansMaximum	0.85
CY2021Q3	cffn	Debt Service Coverage Ratio For Commercial Real Estate Loans Minimum DebtServiceCoverageRatioForCommercialRealEstateLoansMinimum	1.15
CY2021Q3	cffn	Loanto Value Ratiofor Securing Commercial Construction Loans Maximum LoantoValueRatioforSecuringCommercialConstructionLoansMaximum	0.80
CY2021Q3	cffn	Debt Service Coverage Ratio For Commercial Real Estate Loans Minimum DebtServiceCoverageRatioForCommercialRealEstateLoansMinimum	1.15
CY2021Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year One Originated Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear	1953147000	USD
CY2021Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Two Originated Fiscal Year Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear	1204963000	USD
CY2021Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Three Originated Two Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYear	520852000	USD
CY2021Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Four Originated Three Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYear	455353000	USD
CY2021Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Five Originated Four Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYear	485640000	USD
CY2021Q3	us-gaap	Financing Receivable Excluding Accrued Interest Originated More Than Five Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYear	2388212000	USD
CY2021Q3	us-gaap	Financing Receivable Excluding Accrued Interest Revolving FinancingReceivableExcludingAccruedInterestRevolving	92798000	USD
CY2021Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	7100965000	USD
CY2021Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year One Originated Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear	1953147000	USD
CY2021Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Two Originated Fiscal Year Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear	1204963000	USD
CY2021Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Three Originated Two Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYear	520852000	USD
CY2021Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Four Originated Three Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYear	455353000	USD
CY2021Q3	us-gaap	Financing Receivable Excluding Accrued Interest Year Five Originated Four Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYear	485640000	USD
CY2021Q3	us-gaap	Financing Receivable Excluding Accrued Interest Originated More Than Five Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYear	2388212000	USD
CY2021Q3	us-gaap	Financing Receivable Excluding Accrued Interest Revolving FinancingReceivableExcludingAccruedInterestRevolving	92798000	USD
CY2021Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	7100965000	USD
CY2021Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	7100965000	USD
CY2020Q3	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	7234378000	USD
CY2021Q3	us-gaap	Mortgage Loans In Process Of Foreclosure Amount MortgageLoansInProcessOfForeclosureAmount	799000	USD
CY2020Q3	us-gaap	Mortgage Loans In Process Of Foreclosure Amount MortgageLoansInProcessOfForeclosureAmount	1500000	USD
CY2021Q3	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	170000	USD
CY2020Q3	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	183000	USD
CY2021Q3	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	13493000	USD
CY2021Q3	us-gaap	Financing Receivable Nonaccrual No Allowance FinancingReceivableNonaccrualNoAllowance	4763000	USD
CY2020Q3	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	12541000	USD
CY2021	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	7	contract
CY2021	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	1685000	USD
CY2021	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	1576000	USD
CY2020	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	11	contract
CY2020	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	3073000	USD
CY2020	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	3157000	USD
CY2019	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	5	contract
CY2019	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	762000	USD
CY2019	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	763000	USD
CY2021	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	0	contract
CY2021	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	0	USD
CY2020	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	3	contract
CY2020	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	181000	USD
CY2019	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	1	contract
CY2019	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	45000	USD
CY2020Q3	us-gaap	Impaired Financing Receivable With No Related Allowance Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment	19614000	USD
CY2020Q3	us-gaap	Impaired Financing Receivable With No Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance	21201000	USD
CY2020Q3	us-gaap	Impaired Financing Receivable With Related Allowance Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment	1929000	USD
CY2020Q3	us-gaap	Impaired Financing Receivable With Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance	1928000	USD
CY2020Q3	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	323000	USD
CY2020Q3	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	21543000	USD
CY2021	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	237000	USD
CY2020Q3	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	23129000	USD
CY2020Q3	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	323000	USD
CY2020	us-gaap	Impaired Financing Receivable With No Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment	21600000	USD
CY2020	us-gaap	Impaired Financing Receivable With No Related Allowance Interest Income Accrual Method ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod	893000	USD
CY2019	us-gaap	Impaired Financing Receivable With No Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment	23780000	USD
CY2019	us-gaap	Impaired Financing Receivable With No Related Allowance Interest Income Accrual Method ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod	961000	USD
CY2020	us-gaap	Impaired Financing Receivable With Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment	1464000	USD
CY2020	us-gaap	Impaired Financing Receivable With Related Allowance Interest Income Accrual Method ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod	91000	USD
CY2019	us-gaap	Impaired Financing Receivable With Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment	0	USD
CY2019	us-gaap	Impaired Financing Receivable With Related Allowance Interest Income Accrual Method ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod	0	USD
CY2020	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	23064000	USD
CY2020	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	984000	USD
CY2019	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	23780000	USD
CY2019	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	961000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	31527000	USD
CY2021	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	715000	USD
CY2021	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-6465000	USD
CY2021Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	19823000	USD
CY2019Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	9226000	USD
CY2020	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	443000	USD
CY2020	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	444000	USD
CY2020	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	22300000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	31527000	USD
CY2018Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	8463000	USD
CY2019	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	262000	USD
CY2019	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	275000	USD
CY2019	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	750000	USD
CY2019Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	9226000	USD
CY2020Q3	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	7212835000	USD
CY2020Q3	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	21543000	USD
CY2020Q3	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	7234378000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	31204000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	323000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	31527000	USD
CY2021	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-6500000	USD
CY2020Q3	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	0	USD
CY2021	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	-2045000	USD
CY2021Q3	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	5743000	USD
CY2021Q3	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	192900000	USD
CY2020Q3	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	190665000	USD
CY2021Q3	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	93773000	USD
CY2020Q3	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	88790000	USD
CY2021Q3	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	99127000	USD
CY2020Q3	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	101875000	USD
CY2021	us-gaap	Property Plant And Equipment Impairment Or Disposal Disclosure PropertyPlantAndEquipmentImpairmentOrDisposalDisclosure	During the current year, management decided to relocate one of the Bank's branches. As a result, the Company classified as held-for-sale and subsequently sold the property where the branch was previously located.
CY2021	us-gaap	Gain Loss On Disposition Of Assets GainLossOnDispositionOfAssets	-940000	USD
CY2021Q3	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	12700000	USD
CY2021Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	12800000	USD
CY2021Q3	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P21Y9M18D
CY2021Q3	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0251
CY2021	us-gaap	Operating Lease Cost OperatingLeaseCost	1404000	USD
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	1511000	USD
CY2021	us-gaap	Variable Lease Cost VariableLeaseCost	176000	USD
CY2020	us-gaap	Variable Lease Cost VariableLeaseCost	201000	USD
CY2021	us-gaap	Short Term Lease Cost ShortTermLeaseCost	2000	USD
CY2020	us-gaap	Short Term Lease Cost ShortTermLeaseCost	17000	USD
CY2021	us-gaap	Operating Lease Payments OperatingLeasePayments	1301000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	1357000	USD
CY2021Q3	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	1210000	USD
CY2021Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	1224000	USD
CY2021Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	993000	USD
CY2021Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	759000	USD
CY2021Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	711000	USD
CY2021Q3	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	13477000	USD
CY2021Q3	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	18374000	USD
CY2021Q3	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	5552000	USD
CY2021Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	12822000	USD
CY2021Q3	cffn	Investment In Affordable Housing Limited Partnerships InvestmentInAffordableHousingLimitedPartnerships	101200000	USD
CY2020Q3	cffn	Investment In Affordable Housing Limited Partnerships InvestmentInAffordableHousingLimitedPartnerships	89700000	USD
CY2021Q3	us-gaap	Qualified Affordable Housing Project Investments Commitment QualifiedAffordableHousingProjectInvestmentsCommitment	51600000	USD
CY2020Q3	us-gaap	Qualified Affordable Housing Project Investments Commitment QualifiedAffordableHousingProjectInvestmentsCommitment	44500000	USD
CY2021	us-gaap	Affordable Housing Tax Credits Commitment Year To Be Paid AffordableHousingTaxCreditsCommitmentYearToBePaid	2023
CY2021	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	8400000	USD
CY2020	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	7900000	USD
CY2019	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	6800000	USD
CY2021	us-gaap	Affordable Housing Tax Credits And Other Tax Benefits Amount AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount	10500000	USD
CY2020	us-gaap	Affordable Housing Tax Credits And Other Tax Benefits Amount AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount	9800000	USD
CY2019	us-gaap	Affordable Housing Tax Credits And Other Tax Benefits Amount AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount	8600000	USD
CY2021	cffn	Net Income Tax Benefit Low Income Housing Partnerships NetIncomeTaxBenefitLowIncomeHousingPartnerships	2100000	USD
CY2020	cffn	Net Income Tax Benefit Low Income Housing Partnerships NetIncomeTaxBenefitLowIncomeHousingPartnerships	1900000	USD
CY2019	cffn	Net Income Tax Benefit Low Income Housing Partnerships NetIncomeTaxBenefitLowIncomeHousingPartnerships	1800000	USD
CY2020	us-gaap	Affordable Housing Project Investment Write Down Amount AffordableHousingProjectInvestmentWriteDownAmount	0	USD
CY2021	us-gaap	Affordable Housing Project Investment Write Down Amount AffordableHousingProjectInvestmentWriteDownAmount	0	USD
CY2019	us-gaap	Affordable Housing Project Investment Write Down Amount AffordableHousingProjectInvestmentWriteDownAmount	0	USD
CY2021Q3	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	0	USD
CY2021Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	1371000	USD
CY2021Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	1069000	USD
CY2021Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	775000	USD
CY2021Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	523000	USD
CY2021Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	223000	USD
CY2021Q3	us-gaap	Noninterest Bearing Deposit Liabilities Domestic NoninterestBearingDepositLiabilitiesDomestic	543800000	USD
CY2020Q3	us-gaap	Noninterest Bearing Deposit Liabilities Domestic NoninterestBearingDepositLiabilitiesDomestic	451400000	USD
CY2021Q3	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	597400000	USD
CY2020Q3	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	643000000	USD
CY2021	us-gaap	Derivative Average Remaining Maturity1 DerivativeAverageRemainingMaturity1	P4Y1M6D
CY2021Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary By Interest Rate Type Fixed Rate FederalHomeLoanBankAdvancesMaturitiesSummaryByInterestRateTypeFixedRate	1230000000	USD
CY2021Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary By Interest Rate Type Floating Rate FederalHomeLoanBankAdvancesMaturitiesSummaryByInterestRateTypeFloatingRate	365000000	USD
CY2021Q3	us-gaap	Line Of Credit LineOfCredit	0	USD
CY2020Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary By Interest Rate Type Fixed Rate FederalHomeLoanBankAdvancesMaturitiesSummaryByInterestRateTypeFixedRate	1150000000	USD
CY2020Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary By Interest Rate Type Floating Rate FederalHomeLoanBankAdvancesMaturitiesSummaryByInterestRateTypeFloatingRate	640000000	USD
CY2020Q3	us-gaap	Line Of Credit LineOfCredit	0	USD
CY2021	us-gaap	Line Of Credit Facility Expiration Date1 LineOfCreditFacilityExpirationDate1	2021-11-12
CY2021Q3	us-gaap	Advances From Federal Home Loan Banks AdvancesFromFederalHomeLoanBanks	1590000000	USD
CY2020Q3	us-gaap	Advances From Federal Home Loan Banks AdvancesFromFederalHomeLoanBanks	1793000000	USD
CY2021Q3	cffn	Prepayment Penalty On Fhlb Advances PrepaymentPenaltyOnFhlbAdvances	7150000	USD
CY2020Q3	cffn	Prepayment Penalty On Fhlb Advances PrepaymentPenaltyOnFhlbAdvances	3687000	USD
CY2021Q3	us-gaap	Derivative Liability Notional Amount DerivativeLiabilityNotionalAmount	365000000	USD
CY2020Q3	us-gaap	Derivative Liability Notional Amount DerivativeLiabilityNotionalAmount	640000000	USD
CY2021Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary By Interest Rate Type Floating Rate FederalHomeLoanBankAdvancesMaturitiesSummaryByInterestRateTypeFloatingRate	365000000	USD
CY2020Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary By Interest Rate Type Floating Rate FederalHomeLoanBankAdvancesMaturitiesSummaryByInterestRateTypeFloatingRate	640000000	USD
CY2020	us-gaap	Derivative Average Remaining Maturity1 DerivativeAverageRemainingMaturity1	P3Y6M
CY2021Q3	us-gaap	Derivative Fair Value Of Derivative Net DerivativeFairValueOfDerivativeNet	-27700000	USD
CY2020Q3	us-gaap	Derivative Fair Value Of Derivative Net DerivativeFairValueOfDerivativeNet	-53100000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	-13600000	USD
CY2021	us-gaap	Interest Rate Cash Flow Hedge Gain Loss Reclassified To Earnings Net InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet	10000000	USD
CY2021	us-gaap	Loss On Discontinuation Of Cash Flow Hedge Due To Forecasted Transaction Probable Of Not Occurring LossOnDiscontinuationOfCashFlowHedgeDueToForecastedTransactionProbableOfNotOccurring	3600000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	-6300000	USD
CY2021	us-gaap	Derivative Instruments Gain Loss Reclassification From Accumulated Oci To Income Estimated Net Amount To Be Transferred DerivativeInstrumentsGainLossReclassificationFromAccumulatedOCIToIncomeEstimatedNetAmountToBeTransferred	9200000	USD
CY2021Q3	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	28000000	USD
CY2020Q3	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	54600000	USD
CY2021	us-gaap	Loss On Discontinuation Of Cash Flow Hedge Due To Forecasted Transaction Probable Of Not Occurring LossOnDiscontinuationOfCashFlowHedgeDueToForecastedTransactionProbableOfNotOccurring	3600000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Reclassification For Discontinuance Before Tax OtherComprehensiveIncomeLossCashFlowHedgeReclassificationForDiscontinuanceBeforeTax	4800000	USD
CY2021Q3	cffn	Effective Rate Fhlb Advances EffectiveRateFHLBAdvances	0.0103
CY2021Q3	cffn	Fhlb Borrowings Threshold Percentage Of Regulatory Assets FHLBBorrowingsThresholdPercentageOfRegulatoryAssets	0.40
CY2021Q3	cffn	Fhl Bborrowingsthresholdpercentageofregulatoryassetstemporaryincrease FHLBborrowingsthresholdpercentageofregulatoryassetstemporaryincrease	0.50
CY2021Q3	cffn	Fhlb Percentage Of Regulatory Assets FhlbPercentageOfRegulatoryAssets	0.16
CY2021Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due Within One Year Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueWithinOneYearOfBalanceSheetDate	175000000	USD
CY2021Q3	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	1655108000	USD
CY2021Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due From One To Two Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromOneToTwoYearsOfBalanceSheetDate	300000000	USD
CY2021Q3	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	593098000	USD
CY2021Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due From Two To Three Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromTwoToThreeYearsOfBalanceSheetDate	315000000	USD
CY2021Q3	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	313206000	USD
CY2021Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due From Three To Four Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromThreeToFourYearsOfBalanceSheetDate	400000000	USD
CY2021Q3	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	129805000	USD
CY2021Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due From Four To Five Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromFourToFiveYearsOfBalanceSheetDate	250000000	USD
CY2021Q3	us-gaap	Time Deposit Maturities Year Five TimeDepositMaturitiesYearFive	51530000	USD
CY2021Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due After Five Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueAfterFiveYearsOfBalanceSheetDate	150000000	USD
CY2021Q3	us-gaap	Time Deposit Maturities After Year Five TimeDepositMaturitiesAfterYearFive	844000	USD
CY2021Q3	us-gaap	Advances From Federal Home Loan Banks AdvancesFromFederalHomeLoanBanks	1590000000	USD
CY2021Q3	us-gaap	Interest Bearing Domestic Deposit Certificates Of Deposits InterestBearingDomesticDepositCertificatesOfDeposits	2743591000	USD
CY2021	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	17586000	USD
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	17610000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	22030000	USD
CY2021	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	4028000	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	4068000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	4742000	USD
CY2021	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	21614000	USD
CY2020	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	21678000	USD
CY2019	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	26772000	USD
CY2021	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-1405000	USD
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-4857000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-456000	USD
CY2021	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-263000	USD
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-731000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	95000	USD
CY2021	us-gaap	Deferred Federal State And Local Tax Expense Benefit DeferredFederalStateAndLocalTaxExpenseBenefit	-1668000	USD
CY2020	us-gaap	Deferred Federal State And Local Tax Expense Benefit DeferredFederalStateAndLocalTaxExpenseBenefit	-5588000	USD
CY2019	us-gaap	Deferred Federal State And Local Tax Expense Benefit DeferredFederalStateAndLocalTaxExpenseBenefit	-361000	USD
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	19946000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	16090000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	26411000	USD
CY2021	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.208
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.200
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.219
CY2021	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	20166000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	16932000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	25337000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2021	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	3102000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.032
CY2020	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	2626000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.033
CY2019	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	4024000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.033
CY2021	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	2085000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.021
CY2020	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	1897000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.024
CY2019	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	1745000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.014
CY2021	cffn	Esop Related Expenses Net EsopRelatedExpensesNet	-662000	USD
CY2021	cffn	Effective Income Tax Rate Esop Related Expenses Net EffectiveIncomeTaxRateEsopRelatedExpensesNet	-0.007
CY2019	cffn	Effective Income Tax Rate Reconciliation Boli Income EffectiveIncomeTaxRateReconciliationBOLIIncome	0
CY2021	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-575000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.006
CY2020	cffn	Esop Related Expenses Net EsopRelatedExpensesNet	-525000	USD
CY2020	cffn	Effective Income Tax Rate Esop Related Expenses Net EffectiveIncomeTaxRateEsopRelatedExpensesNet	-0.006
CY2019	cffn	Esop Related Expenses Net EsopRelatedExpensesNet	-757000	USD
CY2019	cffn	Effective Income Tax Rate Esop Related Expenses Net EffectiveIncomeTaxRateEsopRelatedExpensesNet	-0.006
CY2021	cffn	Income Tax Reconciliation Boli Income IncomeTaxReconciliationBOLIIncome	0	USD
CY2021	cffn	Effective Income Tax Rate Reconciliation Boli Income EffectiveIncomeTaxRateReconciliationBOLIIncome	0
CY2020	cffn	Income Tax Reconciliation Boli Income IncomeTaxReconciliationBOLIIncome	636000	USD
CY2020	cffn	Effective Income Tax Rate Reconciliation Boli Income EffectiveIncomeTaxRateReconciliationBOLIIncome	0.008
CY2019	cffn	Income Tax Reconciliation Boli Income IncomeTaxReconciliationBOLIIncome	0	USD
CY2020	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-410000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.005
CY2019	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-448000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.004
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	19946000	USD
CY2021	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.208
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	16090000	USD
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.200
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	26411000	USD
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.219
CY2021Q3	us-gaap	Deferred Tax Assets Derivative Instruments DeferredTaxAssetsDerivativeInstruments	6763000	USD
CY2020Q3	us-gaap	Deferred Tax Assets Derivative Instruments DeferredTaxAssetsDerivativeInstruments	12916000	USD
CY2021Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	4163000	USD
CY2020Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	6553000	USD
CY2021Q3	cffn	Deferred Tax Assets Operating Lease Liabilities DeferredTaxAssetsOperatingLeaseLiabilities	3129000	USD
CY2020Q3	cffn	Deferred Tax Assets Operating Lease Liabilities DeferredTaxAssetsOperatingLeaseLiabilities	3590000	USD
CY2021Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits	2017000	USD
CY2020Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits	1622000	USD
CY2021Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Postretirement Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits	1422000	USD
CY2020Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Postretirement Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits	1360000	USD
CY2021Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsReserves	1402000	USD
CY2020Q3	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	3588000	USD
CY2021Q3	cffn	Deferred Tax Liabilities Allowance For Credit Losses DeferredTaxLiabilitiesAllowanceForCreditLosses	2892000	USD
CY2020Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsReserves	0	USD
CY2021Q3	us-gaap	Deferred Tax Assets Investments DeferredTaxAssetsInvestments	522000	USD
CY2020Q3	us-gaap	Deferred Tax Assets Investments DeferredTaxAssetsInvestments	655000	USD
CY2021Q3	us-gaap	Deferred Tax Assets Deferred Income DeferredTaxAssetsDeferredIncome	287000	USD
CY2020Q3	us-gaap	Deferred Tax Assets Deferred Income DeferredTaxAssetsDeferredIncome	577000	USD
CY2021Q3	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	417000	USD
CY2020Q3	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	2717000	USD
CY2021Q3	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	20122000	USD
CY2020Q3	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	29990000	USD
CY2021Q3	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	72000	USD
CY2020Q3	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	1808000	USD
CY2021Q3	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	20050000	USD
CY2020Q3	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	28182000	USD
CY2021Q3	cffn	Deferred Tax Liabilities Federal Home Loan Bank Stock Dividends DeferredTaxLiabilitiesFederalHomeLoanBankStockDividends	12563000	USD
CY2020Q3	cffn	Deferred Tax Liabilities Federal Home Loan Bank Stock Dividends DeferredTaxLiabilitiesFederalHomeLoanBankStockDividends	15699000	USD
CY2021Q3	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	4256000	USD
CY2020Q3	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	4625000	USD
CY2019Q3	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0	USD
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CY2020Q3	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	8180000	USD
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CY2020Q3	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	1475000	USD
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CY2020Q3	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	970000	USD
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CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	16600000	USD
CY2021	cffn	Interchange Network Charges InterchangeNetworkCharges	3600000	USD
CY2020	cffn	Interchange Network Charges InterchangeNetworkCharges	3200000	USD
CY2019	cffn	Interchange Network Charges InterchangeNetworkCharges	3400000	USD

Files In Submission

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$CFFN
Capitol Federal Financial, Inc. Stock $cffn

2021 Q3 Form 10-K Financial Statement

#000149090621000065 Filed on November 24, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CFFN Capitol Federal Financial, Inc. Stock $cffn

2021 Q3 Form 10-K Financial Statement

#000149090621000065 Filed on November 24, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CFFN
Capitol Federal Financial, Inc. Stock $cffn