$BKU
BankUnited, Inc. Stock $bku

$bku Overview Financials Valuation SEC Filings Company Website

2021 Q4 Form 10-K Financial Statement

#000150400822000009 Filed on February 24, 2022

Income Statement

Concept	2021 Q4	2021 Q3	2021
Revenue	$237.9M	$234.3M	$959.4M
YoY Change	-5.28%	-7.95%	-10.13%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development		$16.69M	$67.50M
YoY Change		8.11%	16.16%
% of Gross Profit
Depreciation & Amortization	$22.40M	$19.00M	$78.50M
YoY Change	23.76%	1.6%	8.28%
% of Gross Profit
Operating Expenses		$16.69M	$67.50M
YoY Change		8.11%	16.16%
Operating Profit
YoY Change
Interest Expense	$31.86M	$39.22M	$163.8M
YoY Change	-44.84%	-41.54%	-48.15%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$63.53M	$114.4M	$449.4M
YoY Change	-40.61%	33.16%	80.22%
Income Tax	-$61.72M	$27.46M	$34.40M
% Of Pretax Income	-97.16%	24.0%	7.66%
Net Earnings	$125.3M	$86.94M	$415.0M
YoY Change	46.09%	30.62%	109.74%
Net Earnings / Revenue	52.66%	37.1%	43.25%
Basic Earnings Per Share	$1.42	$0.94	$4.52
Diluted Earnings Per Share	$1.41	$0.94	$4.52
COMMON SHARES
Basic Shares Outstanding	89.09M shares	90.85M shares	90.40M shares
Diluted Shares Outstanding		91.03M shares	90.40M shares

Balance Sheet

Concept	2021 Q4	2021 Q3	2021
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$314.9M	$507.0M
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	$56.73M	$660.0M	$804.0M
YoY Change	-5.64%	-2.37%	-4.06%
Goodwill
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	$35.82B	$35.31B	$35.82B
YoY Change	2.3%	0.79%	2.3%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses			$90.00M
YoY Change			-4.26%
Deferred Revenue
YoY Change
Short-Term Debt	$199.0M	$199.0M	$199.0M
YoY Change	10.56%	10.56%	10.56%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$199.0M	$199.0M	$90.00M
YoY Change	10.56%	10.56%	-4.26%
LONG-TERM LIABILITIES
Long-Term Debt	$721.0M	$722.0M	$721.0M
YoY Change	-0.14%	-49.05%	-0.14%
Other Long-Term Liabilities	$514.0M	$742.0M	$425.0M
YoY Change	1.58%	35.9%	3.16%
Total Long-Term Liabilities	$1.235B	$1.464B	$1.146B
YoY Change	0.57%	-25.42%	1.06%
TOTAL LIABILITIES
Total Short-Term Liabilities	$199.0M	$199.0M	$90.00M
Total Long-Term Liabilities	$1.235B	$1.464B	$1.146B
Total Liabilities	$32.78B	$32.21B	$32.78B
YoY Change	2.34%	0.14%	2.34%
SHAREHOLDERS EQUITY
Retained Earnings	$2.345B	$2.240B
YoY Change	16.47%	14.85%
Common Stock	$856.0K	$900.0K
YoY Change	-8.06%	-2.6%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$3.038B	$3.097B	$3.038B
YoY Change
Total Liabilities & Shareholders Equity	$35.82B	$35.31B	$35.82B
YoY Change	2.3%	0.79%	2.3%

Cashflow Statement

Concept	2021 Q4	2021 Q3	2021
OPERATING ACTIVITIES
Net Income	$125.3M	$86.94M	$415.0M
YoY Change	46.09%	30.62%	109.74%
Depreciation, Depletion And Amortization	$22.40M	$19.00M	$78.50M
YoY Change	23.76%	1.6%	8.28%
Cash From Operating Activities	$267.2M	$375.2M	$1.220B
YoY Change	16.53%	19.45%	41.2%
INVESTING ACTIVITIES
Capital Expenditures	$0.00	-$5.300M	-$44.20M
YoY Change		960.0%	125.51%
Acquisitions
YoY Change
Other Investing Activities	-$1.008B	-$82.30M	$11.20M
YoY Change	1932.66%	-80.69%	-33.34%
Cash From Investing Activities	-$1.008B	-$87.60M	-$1.638B
YoY Change	1932.66%	-79.47%	-37.5%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net			$318.5M
YoY Change			215.43%
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	548.9M	-676.0M	$334.9M
YoY Change	-461.83%	-942.89%	-82.73%
NET CHANGE
Cash From Operating Activities	267.2M	375.2M	$1.220B
Cash From Investing Activities	-1.008B	-87.60M	-$1.638B
Cash From Financing Activities	548.9M	-676.0M	$334.9M
Net Change In Cash	-192.1M	-388.4M	-$82.86M
YoY Change	-786.07%	1098.77%	-145.27%
FREE CASH FLOW
Cash From Operating Activities	$267.2M	$375.2M	$1.220B
Capital Expenditures	$0.00	-$5.300M	-$44.20M
Free Cash Flow	$267.2M	$380.5M	$1.264B
YoY Change	16.53%	20.95%	43.07%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2021	dei	Entity Central Index Key EntityCentralIndexKey	0001504008
CY2021	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2021
CY2021	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2021	dei	Amendment Flag AmendmentFlag	false
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CY2021Q4	us-gaap	Finance Lease Liability Statement Of Financial Position Extensible List FinanceLeaseLiabilityStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2021-01-31#LongTermDebtAndCapitalLeaseObligations
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CY2021	dei	Document Type DocumentType	10-K
CY2021	dei	Document Annual Report DocumentAnnualReport	true
CY2021	dei	Document Transition Report DocumentTransitionReport	false
CY2021	dei	Document Period End Date DocumentPeriodEndDate	2021-12-31
CY2021	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2021	dei	Entity File Number EntityFileNumber	001-35039
CY2021	dei	Entity Registrant Name EntityRegistrantName	BankUnited, Inc.
CY2021	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2021	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	27-0162450
CY2021	dei	Entity Address Address Line1 EntityAddressAddressLine1	14817 Oak Lane
CY2021	dei	Entity Address City Or Town EntityAddressCityOrTown	Miami Lakes
CY2021	dei	Entity Address State Or Province EntityAddressStateOrProvince	FL
CY2021	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	33016
CY2021	dei	City Area Code CityAreaCode	305
CY2021	dei	Local Phone Number LocalPhoneNumber	569-2000
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CY2021	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
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CY2021	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2021	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
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CY2021	dei	Auditor Name AuditorName	Deloitte and Touche LLP
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CY2020	us-gaap	Net Income Loss NetIncomeLoss	197853000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	313098000	USD
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	4.52
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.06
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.14
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	4.52
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.06
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.13
CY2021	us-gaap	Net Income Loss NetIncomeLoss	414984000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	197853000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	313098000	USD
CY2021	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-54228000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	46045000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	37616000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	6712000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	10431000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	13625000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-60940000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	35614000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	23991000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	22207000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	-87402000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	-58760000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	-38545000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	-34463000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	1931000	USD
CY2021	bku	Other Comprehensive Income Loss Cash Flow Hedge Reclassification For Discontinuance Net Of Tax OtherComprehensiveIncomeLossCashFlowHedgeReclassificationForDiscontinuanceNetOfTax	33400000	USD
CY2020	bku	Other Comprehensive Income Loss Cash Flow Hedge Reclassification For Discontinuance Net Of Tax OtherComprehensiveIncomeLossCashFlowHedgeReclassificationForDiscontinuanceNetOfTax	0	USD
CY2019	bku	Other Comprehensive Income Loss Cash Flow Hedge Reclassification For Discontinuance Net Of Tax OtherComprehensiveIncomeLossCashFlowHedgeReclassificationForDiscontinuanceNetOfTax	0	USD
CY2021	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	94152000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	-52939000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	-60691000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	33212000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-17325000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-36700000	USD
CY2021	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	448196000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	180528000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	276398000	USD
CY2021	us-gaap	Net Income Loss NetIncomeLoss	414984000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	197853000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	313098000	USD
CY2021	bku	Amortization Accretion Of Discounts And Premiums AmortizationAccretionOfDiscountsAndPremiums	21205000	USD
CY2020	bku	Amortization Accretion Of Discounts And Premiums AmortizationAccretionOfDiscountsAndPremiums	28246000	USD
CY2019	bku	Amortization Accretion Of Discounts And Premiums AmortizationAccretionOfDiscountsAndPremiums	37319000	USD
CY2021	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-67119000	USD
CY2020	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	178431000	USD
CY2019	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	8904000	USD
CY2021	us-gaap	Gain Loss On Sale Of Loans And Leases GainLossOnSaleOfLoansAndLeases	24394000	USD
CY2020	us-gaap	Gain Loss On Sale Of Loans And Leases GainLossOnSaleOfLoansAndLeases	13170000	USD
CY2019	us-gaap	Gain Loss On Sale Of Loans And Leases GainLossOnSaleOfLoansAndLeases	12119000	USD
CY2021	us-gaap	Gain Loss On Investments GainLossOnInvestments	6446000	USD
CY2020	us-gaap	Gain Loss On Investments GainLossOnInvestments	17767000	USD
CY2019	us-gaap	Gain Loss On Investments GainLossOnInvestments	21174000	USD
CY2021	us-gaap	Share Based Compensation ShareBasedCompensation	23832000	USD
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	20367000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	23367000	USD
CY2021	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	78500000	USD
CY2020	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	72508000	USD
CY2019	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	72425000	USD
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-9015000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-27586000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	24529000	USD
CY2021	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	807097000	USD
CY2020	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	610623000	USD
CY2019	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	412034000	USD
CY2021	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	0	USD
CY2020	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	26196000	USD
CY2019	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	86568000	USD
CY2021	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	148806000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	33383000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-17749000	USD
CY2021	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	172747000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-69266000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-79220000	USD
CY2021	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1220175000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	864168000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	635706000	USD
CY2021	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	5835143000	USD
CY2020	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	4208597000	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	3896234000	USD
CY2021	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	2586385000	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	1352788000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	1370584000	USD
CY2021	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	2286600000	USD
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	1503498000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	2975259000	USD
CY2021	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	62137000	USD
CY2020	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	134938000	USD
CY2019	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	411825000	USD
CY2021	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	122143000	USD
CY2020	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	192737000	USD
CY2019	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	425213000	USD
CY2021	us-gaap	Payments To Acquire Loans Held For Investment PaymentsToAcquireLoansHeldForInvestment	4843231000	USD
CY2020	us-gaap	Payments To Acquire Loans Held For Investment PaymentsToAcquireLoansHeldForInvestment	3157659000	USD
CY2019	us-gaap	Payments To Acquire Loans Held For Investment PaymentsToAcquireLoansHeldForInvestment	2197484000	USD
CY2021	bku	Payments For Proceeds From Loan Originations Prepayments And Resolutions Net PaymentsForProceedsFromLoanOriginationsPrepaymentsAndResolutionsNet	-3856932000	USD
CY2020	bku	Payments For Proceeds From Loan Originations Prepayments And Resolutions Net PaymentsForProceedsFromLoanOriginationsPrepaymentsAndResolutionsNet	-1819139000	USD
CY2019	bku	Payments For Proceeds From Loan Originations Prepayments And Resolutions Net PaymentsForProceedsFromLoanOriginationsPrepaymentsAndResolutionsNet	-477805000	USD
CY2021	us-gaap	Proceeds From Sale Of Loans Held For Investment ProceedsFromSaleOfLoansHeldForInvestment	305929000	USD
CY2020	us-gaap	Proceeds From Sale Of Loans Held For Investment ProceedsFromSaleOfLoansHeldForInvestment	48721000	USD
CY2019	us-gaap	Proceeds From Sale Of Loans Held For Investment ProceedsFromSaleOfLoansHeldForInvestment	265582000	USD
CY2021	us-gaap	Payments To Acquire Equipment On Lease PaymentsToAcquireEquipmentOnLease	44179000	USD
CY2020	us-gaap	Payments To Acquire Equipment On Lease PaymentsToAcquireEquipmentOnLease	19597000	USD
CY2019	us-gaap	Payments To Acquire Equipment On Lease PaymentsToAcquireEquipmentOnLease	63786000	USD
CY2021	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	11204000	USD
CY2020	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	16807000	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	20610000	USD
CY2021	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1637905000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2620715000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1075496000	USD
CY2021	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	1942286000	USD
CY2020	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	3101225000	USD
CY2019	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	920368000	USD
CY2021	us-gaap	Increase Decrease In Federal Funds Purchased IncreaseDecreaseInFederalFundsPurchased	-19000000	USD
CY2020	us-gaap	Increase Decrease In Federal Funds Purchased IncreaseDecreaseInFederalFundsPurchased	-80000000	USD
CY2019	us-gaap	Increase Decrease In Federal Funds Purchased IncreaseDecreaseInFederalFundsPurchased	75000000	USD
CY2021	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	946000000	USD
CY2020	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	3857000000	USD
CY2019	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	4512000000	USD
CY2021	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	2162000000	USD
CY2020	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	5217000000	USD
CY2019	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	4827000000	USD
CY2021	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	0	USD
CY2020	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	293858000	USD
CY2019	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	0	USD
CY2021	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	85790000	USD
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	86522000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	84083000	USD
CY2021	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	25000	USD
CY2020	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	19611000	USD
CY2019	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	5817000	USD
CY2021	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	318499000	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	100972000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	154030000	USD
CY2021	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-6151000	USD
CY2020	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-7610000	USD
CY2019	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-25682000	USD
CY2021	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	334871000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	1939590000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	272390000	USD
CY2021	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-82859000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	183043000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-167400000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	397716000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	214673000	USD
CY2021	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	83357000	USD
CY2021	us-gaap	Stock Issued During Period Value Share Based Compensation Gross StockIssuedDuringPeriodValueShareBasedCompensationGross	14340000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	382073000	USD
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	314857000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	397716000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	214673000	USD
CY2021	us-gaap	Interest Paid Net InterestPaidNet	169291000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	336991000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	518856000	USD
CY2021	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	248473000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	8637000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	229000	USD
CY2021	us-gaap	Transfer Of Portfolio Loans And Leases To Held For Sale1 TransferOfPortfolioLoansAndLeasesToHeldForSale1	1064090000	USD
CY2020	us-gaap	Transfer Of Portfolio Loans And Leases To Held For Sale1 TransferOfPortfolioLoansAndLeasesToHeldForSale1	602198000	USD
CY2019	us-gaap	Transfer Of Portfolio Loans And Leases To Held For Sale1 TransferOfPortfolioLoansAndLeasesToHeldForSale1	536227000	USD
CY2021	bku	Dividends Declared And Payable DividendsDeclaredAndPayable	19876000	USD
CY2020	bku	Dividends Declared And Payable DividendsDeclaredAndPayable	22309000	USD
CY2019	bku	Dividends Declared And Payable DividendsDeclaredAndPayable	20775000	USD
CY2020	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	19611000	USD
CY2020	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	100972000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	2983012000	USD
CY2021	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	448196000	USD
CY2021	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.92
CY2021	us-gaap	Stock Issued During Period Value Share Based Compensation Forfeited StockIssuedDuringPeriodValueShareBasedCompensationForfeited	5956000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	2923833000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	276398000	USD
CY2019	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.84
CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	83185000	USD
CY2019	us-gaap	Stock Issued During Period Value Share Based Compensation Gross StockIssuedDuringPeriodValueShareBasedCompensationGross	18460000	USD
CY2019	us-gaap	Stock Issued During Period Value Share Based Compensation Forfeited StockIssuedDuringPeriodValueShareBasedCompensationForfeited	6514000	USD
CY2019	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	5817000	USD
CY2019	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	154030000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	2980779000	USD
CY2019Q4	us-gaap	Shares Outstanding SharesOutstanding	0	shares
CY2020Q1	us-gaap	Stockholders Equity StockholdersEquity	2956962000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	180528000	USD
CY2020	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.92
CY2020	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	88056000	USD
CY2020	us-gaap	Stock Issued During Period Value Share Based Compensation Gross StockIssuedDuringPeriodValueShareBasedCompensationGross	19558000	USD
CY2020	us-gaap	Stock Issued During Period Value Share Based Compensation Forfeited StockIssuedDuringPeriodValueShareBasedCompensationForfeited	4619000	USD
CY2021	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	25000	USD
CY2021	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	318499000	USD
CY2021Q4	us-gaap	Stockholders Equity StockholdersEquity	3037761000	USD
CY2021Q4	us-gaap	Assets Assets	35800000000	USD
CY2021Q4	bku	Number Of Operating Counties NumberOfOperatingCounties	13	rental
CY2021	us-gaap	Use Of Estimates UseOfEstimates	<div style="margin-bottom:8pt;margin-top:12pt;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Accounting Estimates</span></div><div style="margin-bottom:8pt;margin-top:8pt;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In preparing the consolidated financial statements, management is required to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues, and expenses and disclosures of contingent assets and liabilities. Actual results could differ significantly from these estimates. </span></div>The most significant estimate impacting the Company's consolidated financial statements is the ACL.
CY2021	us-gaap	Net Income Loss NetIncomeLoss	414984000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	197853000	USD
CY2020	us-gaap	Participating Securities Distributed And Undistributed Earnings Loss Basic ParticipatingSecuritiesDistributedAndUndistributedEarningsLossBasic	8882000	USD
CY2020	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	24608	shares
CY2019	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	202890	shares
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	90400322	shares
CY2019	us-gaap	Net Income Loss NetIncomeLoss	313098000	USD
CY2021	us-gaap	Participating Securities Distributed And Undistributed Earnings Loss Basic ParticipatingSecuritiesDistributedAndUndistributedEarningsLossBasic	5991000	USD
CY2019	us-gaap	Participating Securities Distributed And Undistributed Earnings Loss Basic ParticipatingSecuritiesDistributedAndUndistributedEarningsLossBasic	13371000	USD
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	408993000	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	188971000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	299727000	USD
CY2021	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	91612243	shares
CY2020	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	92869736	shares
CY2019	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	96581290	shares
CY2021	us-gaap	Weighted Average Number Of Shares Common Stock Subject To Repurchase Or Cancellation WeightedAverageNumberOfSharesCommonStockSubjectToRepurchaseOrCancellation	1212055	shares
CY2020	us-gaap	Weighted Average Number Of Shares Common Stock Subject To Repurchase Or Cancellation WeightedAverageNumberOfSharesCommonStockSubjectToRepurchaseOrCancellation	1163480	shares
CY2019	us-gaap	Weighted Average Number Of Shares Common Stock Subject To Repurchase Or Cancellation WeightedAverageNumberOfSharesCommonStockSubjectToRepurchaseOrCancellation	1127275	shares
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	90400188	shares
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	91706256	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	95454015	shares
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	4.52
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.06
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.14
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	408993000	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	188971000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	299727000	USD
CY2021	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	585000	USD
CY2020	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	123000	USD
CY2019	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	175000	USD
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	408408000	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	188848000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	299552000	USD
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	90400188	shares
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	91706256	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	95454015	shares
CY2021	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	134	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	91730864	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	95656905	shares
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	4.52
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.06
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.13
CY2021	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1804973	shares
CY2020	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1638642	shares
CY2019	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1050455	shares
CY2019Q4	bku	Dividend Equivalent Rights DividendEquivalentRights	3023314	shares
CY2020Q4	bku	Dividend Equivalent Rights DividendEquivalentRights	3023314	shares
CY2021Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	9929586000	USD
CY2021Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	55446000	USD
CY2021Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	51611000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	9933421000	USD
CY2021Q4	bku	Debt Securities Available For Sale Securities And Held To Maturity Securities Amortized Cost Basis DebtSecuritiesAvailableForSaleSecuritiesAndHeldToMaturitySecuritiesAmortizedCostBasis	9939586000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale And Held To Maturity DebtSecuritiesAvailableForSaleAndHeldToMaturity	9943421000	USD
CY2021Q4	us-gaap	Investments Investments	10064198000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	8976774000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	117076000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	31441000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	9062409000	USD
CY2020Q4	bku	Debt Securities Available For Sale Securities And Held To Maturity Securities Amortized Cost Basis DebtSecuritiesAvailableForSaleSecuritiesAndHeldToMaturitySecuritiesAmortizedCostBasis	8986774000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale And Held To Maturity DebtSecuritiesAvailableForSaleAndHeldToMaturity	9072409000	USD
CY2020Q4	us-gaap	Investments Investments	9176683000	USD
CY2021Q4	bku	Number Of Held To Maturity Securities NumberOfHeldToMaturitySecurities	1
CY2020Q4	bku	Number Of Held To Maturity Securities NumberOfHeldToMaturitySecurities	1
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	1651375000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	1646232000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	5915112000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	5929475000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	1933775000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	1929493000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	429324000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	428221000	USD
CY2021Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	9929586000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	9933421000	USD
CY2021	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	2286600000	USD
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	1503498000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	2975259000	USD
CY2021	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	10005000	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	14441000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	21961000	USD
CY2021	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	995000	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	440000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	3424000	USD
CY2021	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	9010000	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	14001000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	18537000	USD
CY2021	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-2564000	USD
CY2020	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	3766000	USD
CY2019	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	2637000	USD
CY2021	us-gaap	Debt And Equity Securities Gain Loss DebtAndEquitySecuritiesGainLoss	6446000	USD
CY2020	us-gaap	Debt And Equity Securities Gain Loss DebtAndEquitySecuritiesGainLoss	17767000	USD
CY2019	us-gaap	Debt And Equity Securities Gain Loss DebtAndEquitySecuritiesGainLoss	21174000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	4098232000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	32595000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	1225140000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	19016000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	5323372000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	51611000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	2165618000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	16966000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	1158153000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	14475000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	3323771000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	31441000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	244	security
CY2021Q4	bku	Number Of Securities Amount Of Impairment Insignificant NumberOfSecuritiesAmountOfImpairmentInsignificant	72	security
CY2021Q4	bku	Availableforsalesecurities Gross Unrealized Loss Considered Insignificantfor Otti Analysis AvailableforsalesecuritiesGrossUnrealizedLossConsideredInsignificantforOTTIAnalysis	600000	USD
CY2021Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	23765053000	USD
CY2021Q4	bku	Percent Of Total Loans PercentOfTotalLoans	1.000
CY2020Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	23866042000	USD
CY2020Q4	bku	Percent Of Total Loans PercentOfTotalLoans	1.000
CY2021Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	126457000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	257323000	USD
CY2021Q4	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	23638596000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	23608719000	USD
CY2021Q4	us-gaap	Financing Receivable Deferred Income FinancingReceivableDeferredIncome	67000000	USD
CY2020Q4	us-gaap	Financing Receivable Deferred Income FinancingReceivableDeferredIncome	39000000	USD
CY2021	us-gaap	Financing Receivable Purchased With Credit Deterioration Discount Premium FinancingReceivablePurchasedWithCreditDeteriorationDiscountPremium	-60000000	USD
CY2020	us-gaap	Financing Receivable Purchased With Credit Deterioration Discount Premium FinancingReceivablePurchasedWithCreditDeteriorationDiscountPremium	-115000000	USD
CY2021Q4	us-gaap	Pledged Financial Instruments Not Separately Reported Loans Receivable Pledged For Federal Home Loan Bank Debt PledgedFinancialInstrumentsNotSeparatelyReportedLoansReceivablePledgedForFederalHomeLoanBankDebt	10600000000	USD
CY2020Q4	us-gaap	Pledged Financial Instruments Not Separately Reported Loans Receivable Pledged For Federal Home Loan Bank Debt PledgedFinancialInstrumentsNotSeparatelyReportedLoansReceivablePledgedForFederalHomeLoanBankDebt	9600000000	USD
CY2021Q4	us-gaap	Interest Receivable InterestReceivable	98000000	USD
CY2020Q4	us-gaap	Interest Receivable InterestReceivable	99000000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	257323000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	108671000	USD
CY2018Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	109931000	USD
CY2021	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	71250000	USD
CY2020	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	69602000	USD
CY2019	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	17541000	USD
CY2021	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	4840000	USD
CY2020	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	8610000	USD
CY2019	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	7377000	USD
CY2021Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	126457000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	257323000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	108671000	USD
CY2021	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	-1235000	USD
CY2020	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	-5572000	USD
CY2021	us-gaap	Provision For Other Credit Losses ProvisionForOtherCreditLosses	364000	USD
CY2020	us-gaap	Provision For Other Credit Losses ProvisionForOtherCreditLosses	364000	USD
CY2021	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-67119000	USD
CY2020	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	178431000	USD
CY2021Q4	us-gaap	Financing Receivable Before Allowance For Credit Loss And Fee FinancingReceivableBeforeAllowanceForCreditLossAndFee	23765053000	USD
CY2020Q4	us-gaap	Financing Receivable Before Allowance For Credit Loss And Fee FinancingReceivableBeforeAllowanceForCreditLossAndFee	23866042000	USD
CY2021Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	730000000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	562000000	USD
CY2021Q4	us-gaap	Loans And Leases Receivable Impaired Nonperforming Nonaccrual Of Interest LoansAndLeasesReceivableImpairedNonperformingNonaccrualOfInterest	205885000	USD
CY2021Q4	us-gaap	Financing Receivable Nonaccrual No Allowance FinancingReceivableNonaccrualNoAllowance	69195000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Impaired Nonperforming Nonaccrual Of Interest LoansAndLeasesReceivableImpairedNonperformingNonaccrualOfInterest	244453000	USD
CY2020Q4	us-gaap	Financing Receivable Nonaccrual No Allowance FinancingReceivableNonaccrualNoAllowance	84195000	USD
CY2021	us-gaap	Loans And Leases Receivable Impaired Interest Lost On Nonaccrual Loans LoansAndLeasesReceivableImpairedInterestLostOnNonaccrualLoans	8000000	USD
CY2020	us-gaap	Loans And Leases Receivable Impaired Interest Lost On Nonaccrual Loans LoansAndLeasesReceivableImpairedInterestLostOnNonaccrualLoans	10900000	USD
CY2019	us-gaap	Loans And Leases Receivable Impaired Interest Lost On Nonaccrual Loans LoansAndLeasesReceivableImpairedInterestLostOnNonaccrualLoans	7500000	USD
CY2021Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	133166000	USD
CY2020Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	156097000	USD
CY2021	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	240
CY2021	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	47910000	USD
CY2021	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	84
CY2021	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	14317000	USD
CY2020	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	211
CY2020	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	51387000	USD
CY2020	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	95
CY2020	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	31454000	USD
CY2019	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	339
CY2019	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	99510000	USD
CY2019	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	115
CY2019	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	27002000	USD
CY2021Q4	bku	Total Lease Liabilities TotalLeaseLiabilities	119751000	USD
CY2020Q4	bku	Total Lease Liabilities TotalLeaseLiabilities	126241000	USD
CY2021Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P6Y10M24D
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P7Y2M12D
CY2021Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P11Y10M24D
CY2020Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P12Y8M12D
CY2021Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.029
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.031
CY2021Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.029
CY2020Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.029
CY2021	us-gaap	Operating Lease Cost OperatingLeaseCost	19646000	USD
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	20112000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	20284000	USD
CY2021	us-gaap	Operating Lease Impairment Loss OperatingLeaseImpairmentLoss	183000	USD
CY2020	us-gaap	Operating Lease Impairment Loss OperatingLeaseImpairmentLoss	108000	USD
CY2019	us-gaap	Operating Lease Impairment Loss OperatingLeaseImpairmentLoss	1278000	USD
CY2021	us-gaap	Lease Cost LeaseCost	19829000	USD
CY2020	us-gaap	Lease Cost LeaseCost	20220000	USD
CY2019	us-gaap	Lease Cost LeaseCost	21562000	USD
CY2021	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	2903000	USD
CY2020	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	2841000	USD
CY2019	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	1642000	USD
CY2021	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	866000	USD
CY2020	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	921000	USD
CY2019	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	1002000	USD
CY2021	bku	Totalfinanceleasecost Totalfinanceleasecost	3769000	USD
CY2020	bku	Totalfinanceleasecost Totalfinanceleasecost	3762000	USD
CY2019	bku	Totalfinanceleasecost Totalfinanceleasecost	2644000	USD
CY2021	us-gaap	Variable Lease Cost VariableLeaseCost	4147000	USD
CY2020	us-gaap	Variable Lease Cost VariableLeaseCost	4761000	USD
CY2019	us-gaap	Variable Lease Cost VariableLeaseCost	3950000	USD
CY2021	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	866000	USD
CY2020	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	921000	USD
CY2019	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	1002000	USD
CY2021	us-gaap	Operating Lease Payments OperatingLeasePayments	20056000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	20589000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	20795000	USD
CY2021	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	3215000	USD
CY2020	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	2980000	USD
CY2019	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	2529000	USD
CY2021	bku	Totalcashpaidforamountsincludedinthemeasurementofleaseliabilities Totalcashpaidforamountsincludedinthemeasurementofleaseliabilities	24137000	USD
CY2020	bku	Totalcashpaidforamountsincludedinthemeasurementofleaseliabilities Totalcashpaidforamountsincludedinthemeasurementofleaseliabilities	24490000	USD
CY2019	bku	Totalcashpaidforamountsincludedinthemeasurementofleaseliabilities Totalcashpaidforamountsincludedinthemeasurementofleaseliabilities	24326000	USD
CY2021	bku	Operatingleaseliabilitiesrecognizedfromobtaining Ro Uassets OperatingleaseliabilitiesrecognizedfromobtainingROUassets	13325000	USD
CY2020	bku	Operatingleaseliabilitiesrecognizedfromobtaining Ro Uassets OperatingleaseliabilitiesrecognizedfromobtainingROUassets	9647000	USD
CY2019	bku	Operatingleaseliabilitiesrecognizedfromobtaining Ro Uassets OperatingleaseliabilitiesrecognizedfromobtainingROUassets	15778000	USD
CY2021	bku	Financeleaseliabilitiesrecognizedfromobtaining Ro Uassets FinanceleaseliabilitiesrecognizedfromobtainingROUassets	0	USD
CY2020	bku	Financeleaseliabilitiesrecognizedfromobtaining Ro Uassets FinanceleaseliabilitiesrecognizedfromobtainingROUassets	373000	USD
CY2019	bku	Financeleaseliabilitiesrecognizedfromobtaining Ro Uassets FinanceleaseliabilitiesrecognizedfromobtainingROUassets	27415000	USD
CY2021	bku	Totalleaseliabilitiesrecognizedfromobtaining Ro Uassets TotalleaseliabilitiesrecognizedfromobtainingROUassets	13325000	USD
CY2020	bku	Totalleaseliabilitiesrecognizedfromobtaining Ro Uassets TotalleaseliabilitiesrecognizedfromobtainingROUassets	10020000	USD
CY2019	bku	Totalleaseliabilitiesrecognizedfromobtaining Ro Uassets TotalleaseliabilitiesrecognizedfromobtainingROUassets	147257000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	18383000	USD
CY2021Q4	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	2650000	USD
CY2021Q4	bku	Total Lease Liability Payments Due Next Twelve Months TotalLeaseLiabilityPaymentsDueNextTwelveMonths	21033000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	16243000	USD
CY2021Q4	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	2666000	USD
CY2021Q4	bku	Total Lease Liability Payments Due Year Two TotalLeaseLiabilityPaymentsDueYearTwo	18909000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	14517000	USD
CY2021Q4	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	2701000	USD
CY2021Q4	bku	Total Lease Liability Payments Due Year Three TotalLeaseLiabilityPaymentsDueYearThree	17218000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	11872000	USD
CY2021Q4	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	2774000	USD
CY2021Q4	bku	Total Lease Liability Payments Due Year Four TotalLeaseLiabilityPaymentsDueYearFour	14646000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	10547000	USD
CY2021Q4	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	2849000	USD
CY2021Q4	bku	Total Lease Liability Payments Due Year Five TotalLeaseLiabilityPaymentsDueYearFive	13396000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	27585000	USD
CY2021Q4	us-gaap	Finance Lease Liability Payments Due After Year Five FinanceLeaseLiabilityPaymentsDueAfterYearFive	22374000	USD
CY2021Q4	bku	Total Lease Liability Payments Due After Year Five TotalLeaseLiabilityPaymentsDueAfterYearFive	49959000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	99147000	USD
CY2021Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	36014000	USD
CY2021Q4	bku	Total Lease Liability Payments Due TotalLeaseLiabilityPaymentsDue	135161000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	9612000	USD
CY2021Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	5798000	USD
CY2021Q4	bku	Total Lease Liability Undiscounted Excess Amount TotalLeaseLiabilityUndiscountedExcessAmount	15410000	USD
CY2021Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	89535000	USD
CY2020Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable SalesTypeAndDirectFinancingLeasesLeaseReceivable	669863000	USD
CY2021Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	30216000	USD
CY2021Q4	bku	Total Lease Liabilities TotalLeaseLiabilities	119751000	USD
CY2021Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable Payments To Be Received SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceived	703395000	USD
CY2020Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable Payments To Be Received SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceived	727401000	USD
CY2021Q4	us-gaap	Direct Financing Lease Unguaranteed Residual Asset DirectFinancingLeaseUnguaranteedResidualAsset	5109000	USD
CY2020Q4	us-gaap	Direct Financing Lease Unguaranteed Residual Asset DirectFinancingLeaseUnguaranteedResidualAsset	5599000	USD
CY2021Q4	bku	Salestypeordirectfinancingleasegrossinvestment Salestypeordirectfinancingleasegrossinvestment	708504000	USD
CY2020Q4	bku	Salestypeordirectfinancingleasegrossinvestment Salestypeordirectfinancingleasegrossinvestment	733000000	USD
CY2021Q4	us-gaap	Direct Financing Lease Deferred Selling Profit DirectFinancingLeaseDeferredSellingProfit	59511000	USD
CY2020Q4	us-gaap	Direct Financing Lease Deferred Selling Profit DirectFinancingLeaseDeferredSellingProfit	66443000	USD
CY2021Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable Undiscounted Excess Amount SalesTypeAndDirectFinancingLeasesLeaseReceivableUndiscountedExcessAmount	2783000	USD
CY2020Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable Undiscounted Excess Amount SalesTypeAndDirectFinancingLeasesLeaseReceivableUndiscountedExcessAmount	3306000	USD
CY2021Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable SalesTypeAndDirectFinancingLeasesLeaseReceivable	651776000	USD
CY2021Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable Payments To Be Received Next Twelve Months SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedNextTwelveMonths	170397000	USD
CY2021Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable Payments To Be Received Two Years SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedTwoYears	155380000	USD
CY2021Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable Payments To Be Received Three Years SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedThreeYears	99483000	USD
CY2021Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable Payments To Be Received Four Years SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedFourYears	68873000	USD
CY2021Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable Payments To Be Received Five Years SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedFiveYears	52572000	USD
CY2021Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable Payments To Be Received Thereafter SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedThereafter	156690000	USD
CY2021Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable Payments To Be Received SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceived	703395000	USD
CY2021Q4	us-gaap	Property Subject To Or Available For Operating Lease Gross PropertySubjectToOrAvailableForOperatingLeaseGross	848304000	USD
CY2020Q4	us-gaap	Property Subject To Or Available For Operating Lease Gross PropertySubjectToOrAvailableForOperatingLeaseGross	844953000	USD
CY2021Q4	us-gaap	Property Subject To Or Available For Operating Lease Accumulated Depreciation PropertySubjectToOrAvailableForOperatingLeaseAccumulatedDepreciation	207578000	USD
CY2020Q4	us-gaap	Property Subject To Or Available For Operating Lease Accumulated Depreciation PropertySubjectToOrAvailableForOperatingLeaseAccumulatedDepreciation	181436000	USD
CY2019	us-gaap	Direct Financing Lease Lease Income DirectFinancingLeaseLeaseIncome	21865000	USD
CY2021	us-gaap	Lease Income LeaseIncome	71592000	USD
CY2020	us-gaap	Lease Income LeaseIncome	80107000	USD
CY2021Q4	us-gaap	Property Subject To Or Available For Operating Lease Net PropertySubjectToOrAvailableForOperatingLeaseNet	640726000	USD
CY2020Q4	us-gaap	Property Subject To Or Available For Operating Lease Net PropertySubjectToOrAvailableForOperatingLeaseNet	663517000	USD
CY2021	us-gaap	Asset Impairment Charges AssetImpairmentCharges	2800000	USD
CY2020	us-gaap	Asset Impairment Charges AssetImpairmentCharges	700000	USD
CY2019	us-gaap	Asset Impairment Charges AssetImpairmentCharges	1900000	USD
CY2021Q4	us-gaap	Lessor Operating Lease Payments To Be Received Next Twelve Months LessorOperatingLeasePaymentsToBeReceivedNextTwelveMonths	49580000	USD
CY2021Q4	us-gaap	Lessor Operating Lease Payments To Be Received Two Years LessorOperatingLeasePaymentsToBeReceivedTwoYears	42693000	USD
CY2021Q4	us-gaap	Lessor Operating Lease Payments To Be Received Three Years LessorOperatingLeasePaymentsToBeReceivedThreeYears	37714000	USD
CY2021Q4	us-gaap	Lessor Operating Lease Payments To Be Received Four Years LessorOperatingLeasePaymentsToBeReceivedFourYears	31843000	USD
CY2021Q4	us-gaap	Lessor Operating Lease Payments To Be Received Five Years LessorOperatingLeasePaymentsToBeReceivedFiveYears	19795000	USD
CY2021Q4	us-gaap	Lessor Operating Lease Payments To Be Received Thereafter LessorOperatingLeasePaymentsToBeReceivedThereafter	50181000	USD
CY2021Q4	us-gaap	Lessor Operating Lease Payments To Be Received LessorOperatingLeasePaymentsToBeReceived	231806000	USD
CY2021	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	53263000	USD
CY2020	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	59112000	USD
CY2019	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	66631000	USD
CY2021	us-gaap	Direct Financing Lease Lease Income DirectFinancingLeaseLeaseIncome	18329000	USD
CY2020	us-gaap	Direct Financing Lease Lease Income DirectFinancingLeaseLeaseIncome	20995000	USD
CY2019	us-gaap	Lease Income LeaseIncome	88496000	USD
CY2019Q4	bku	Weighted Average Rate Domestic Deposits WeightedAverageRateDomesticDeposits	0.0163
CY2021Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	603000000	USD
CY2020Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	1100000000	USD
CY2021	bku	Noninterest Bearing Deposit Liabilities Domestic Average Balance NoninterestBearingDepositLiabilitiesDomesticAverageBalance	8480964000	USD
CY2021Q4	bku	Weighted Average Rate Non Interest Bearing Domestic Deposit WeightedAverageRateNonInterestBearingDomesticDeposit	0
CY2020	bku	Noninterest Bearing Deposit Liabilities Domestic Average Balance NoninterestBearingDepositLiabilitiesDomesticAverageBalance	5760309000	USD
CY2020Q4	bku	Weighted Average Rate Non Interest Bearing Domestic Deposit WeightedAverageRateNonInterestBearingDomesticDeposit	0
CY2019	bku	Noninterest Bearing Deposit Liabilities Domestic Average Balance NoninterestBearingDepositLiabilitiesDomesticAverageBalance	3950612000	USD
CY2019Q4	bku	Weighted Average Rate Non Interest Bearing Domestic Deposit WeightedAverageRateNonInterestBearingDomesticDeposit	0
CY2021	bku	Interest Bearing Deposit Liabilities Domestic Average Balance InterestBearingDepositLiabilitiesDomesticAverageBalance	3027649000	USD
CY2021Q4	bku	Weighted Average Rate Interest Bearing Domestic Deposit WeightedAverageRateInterestBearingDomesticDeposit	0.0028
CY2020	bku	Interest Bearing Deposit Liabilities Domestic Average Balance InterestBearingDepositLiabilitiesDomesticAverageBalance	2582951000	USD
CY2020Q4	bku	Weighted Average Rate Interest Bearing Domestic Deposit WeightedAverageRateInterestBearingDomesticDeposit	0.0075
CY2019	bku	Interest Bearing Deposit Liabilities Domestic Average Balance InterestBearingDepositLiabilitiesDomesticAverageBalance	1824803000	USD
CY2019Q4	bku	Weighted Average Rate Interest Bearing Domestic Deposit WeightedAverageRateInterestBearingDomesticDeposit	0.0137
CY2021Q4	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	2650175000	USD
CY2021Q4	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	126396000	USD
CY2021	bku	Savings And Money Market Average Balance SavingsAndMoneyMarketAverageBalance	13339651000	USD
CY2021Q4	bku	Weighted Average Rate Domestic Deposit Savings And Money Market WeightedAverageRateDomesticDepositSavingsAndMoneyMarket	0.0032
CY2020	bku	Savings And Money Market Average Balance SavingsAndMoneyMarketAverageBalance	10843894000	USD
CY2020Q4	bku	Weighted Average Rate Domestic Deposit Savings And Money Market WeightedAverageRateDomesticDepositSavingsAndMoneyMarket	0.0079
CY2019	bku	Savings And Money Market Average Balance SavingsAndMoneyMarketAverageBalance	10922819000	USD
CY2019Q4	bku	Weighted Average Rate Domestic Deposit Savings And Money Market WeightedAverageRateDomesticDepositSavingsAndMoneyMarket	0.0181
CY2021	bku	Time Deposits Average Balance TimeDepositsAverageBalance	3490082000	USD
CY2021Q4	us-gaap	Weighted Average Rate Domestic Deposit Time Deposits WeightedAverageRateDomesticDepositTimeDeposits	0.0046
CY2020	bku	Time Deposits Average Balance TimeDepositsAverageBalance	6617939000	USD
CY2020Q4	us-gaap	Weighted Average Rate Domestic Deposit Time Deposits WeightedAverageRateDomesticDepositTimeDeposits	0.0143
CY2019	bku	Time Deposits Average Balance TimeDepositsAverageBalance	6928499000	USD
CY2019Q4	us-gaap	Weighted Average Rate Domestic Deposit Time Deposits WeightedAverageRateDomesticDepositTimeDeposits	0.0234
CY2021	bku	Deposits Average Balance DepositsAverageBalance	28338346000	USD
CY2021Q4	bku	Weighted Average Rate Domestic Deposits WeightedAverageRateDomesticDeposits	0.0024
CY2020	bku	Deposits Average Balance DepositsAverageBalance	25805093000	USD
CY2020Q4	bku	Weighted Average Rate Domestic Deposits WeightedAverageRateDomesticDeposits	0.0077
CY2019	bku	Deposits Average Balance DepositsAverageBalance	23626733000	USD
CY2021	us-gaap	Interest Expense Time Deposits InterestExpenseTimeDeposits	15964000	USD
CY2021Q4	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	207015000	USD
CY2021Q4	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	87998000	USD
CY2021Q4	us-gaap	Time Deposit Maturities Year Five TimeDepositMaturitiesYearFive	312659000	USD
CY2021Q4	us-gaap	Time Deposits TimeDeposits	3384243000	USD
CY2021Q4	bku	Publicfundsdepositsincludedindeposits Publicfundsdepositsincludedindeposits	2800000000	USD
CY2021Q4	us-gaap	Interest Bearing Domestic Deposit Brokered InterestBearingDomesticDepositBrokered	4600000000	USD
CY2021Q4	bku	Carrying Value Of Investment Securities Available For Sale Pledged As Security For Time Deposits Issued To Subsidiary And Other Public Funds CarryingValueOfInvestmentSecuritiesAvailableForSalePledgedAsSecurityForTimeDepositsIssuedToSubsidiaryAndOtherPublicFunds	974000000	USD
CY2021	us-gaap	Interest Expense Demand Deposit Accounts InterestExpenseDemandDepositAccounts	8550000	USD
CY2020	us-gaap	Interest Expense Demand Deposit Accounts InterestExpenseDemandDepositAccounts	19445000	USD
CY2019	us-gaap	Interest Expense Demand Deposit Accounts InterestExpenseDemandDepositAccounts	25054000	USD
CY2021	bku	Interest Expense Money Market And Savings Deposits InterestExpenseMoneyMarketAndSavingsDeposits	43082000	USD
CY2020	bku	Interest Expense Money Market And Savings Deposits InterestExpenseMoneyMarketAndSavingsDeposits	85572000	USD
CY2019	bku	Interest Expense Money Market And Savings Deposits InterestExpenseMoneyMarketAndSavingsDeposits	197942000	USD
CY2020	us-gaap	Interest Expense Time Deposits InterestExpenseTimeDeposits	94963000	USD
CY2019	us-gaap	Interest Expense Time Deposits InterestExpenseTimeDeposits	162184000	USD
CY2021	us-gaap	Interest Expense Domestic Deposits InterestExpenseDomesticDeposits	67596000	USD
CY2020	us-gaap	Interest Expense Domestic Deposits InterestExpenseDomesticDeposits	199980000	USD
CY2019	us-gaap	Interest Expense Domestic Deposits InterestExpenseDomesticDeposits	385180000	USD
CY2021Q4	bku	Maturingin Next Twelve Months Onemonthorless MaturinginNextTwelveMonthsOnemonthorless	1210000000	USD
CY2021Q4	bku	Maturingin Next Twelve Months Onemonthorless Weighted Average Ratein Percent MaturinginNextTwelveMonthsOnemonthorlessWeightedAverageRateinPercent	0.0018
CY2021Q4	bku	Maturingin Next Twelve Months Overonemonth MaturinginNextTwelveMonthsOveronemonth	595000000	USD
CY2021Q4	bku	Maturingin Next Twelve Months Overonemonth Weighted Average Ratein Percent MaturinginNextTwelveMonthsOveronemonthWeightedAverageRateinPercent	0.0020
CY2021Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due After Five Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueAfterFiveYearsOfBalanceSheetDate	100000000	USD
CY2021Q4	us-gaap	Federal Home Loan Bank Advances Activity For Year Average Interest Rate At Period End FederalHomeLoanBankAdvancesActivityForYearAverageInterestRateAtPeriodEnd	0.0041
CY2021Q4	us-gaap	Advances From Federal Home Loan Banks AdvancesFromFederalHomeLoanBanks	1905000000	USD
CY2021Q4	us-gaap	Pledged Financial Instruments Not Separately Reported Securities For Federal Home Loan Bank PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesForFederalHomeLoanBank	11800000000	USD
CY2021Q4	us-gaap	Long Term Debt LongTermDebt	691200000	USD
CY2020Q4	us-gaap	Long Term Debt LongTermDebt	689932000	USD
CY2021Q4	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	721416000	USD
CY2020Q4	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	722495000	USD
CY2021Q4	us-gaap	Federal Home Loan Bank Advances General Debt Obligations Disclosures Amount Of Available Unused Funds FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresAmountOfAvailableUnusedFunds	7300000000	USD
CY2021Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	220379000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	213261000	USD
CY2021Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	163645000	USD
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	153138000	USD
CY2021Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	56734000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	60123000	USD
CY2021	us-gaap	Depreciation Nonproduction DepreciationNonproduction	16700000	USD
CY2020	us-gaap	Depreciation Nonproduction DepreciationNonproduction	15700000	USD
CY2019	us-gaap	Depreciation Nonproduction DepreciationNonproduction	19200000	USD
CY2021	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	61814000	USD
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	63083000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	58996000	USD
CY2021	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	-18398000	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	16009000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	7373000	USD
CY2021	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	43416000	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	79092000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	66369000	USD
CY2021	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	4348000	USD
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-22387000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	8255000	USD
CY2021	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-13363000	USD
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-5199000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	16274000	USD
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-9015000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-27586000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	24529000	USD
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	34401000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	51506000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	90898000	USD
CY2021	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	94371000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.2100
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	52366000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.2100
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	84839000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.2100
CY2021	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	13203000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.0294
CY2020	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	15722000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.0630
CY2019	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	17950000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.0444
CY2021	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	22197000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.0494
CY2020	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	13413000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.0538
CY2019	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	19956000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.0494
CY2021	bku	Effective Income Tax Rate Reconciliation Uncertain Tax Position Amount EffectiveIncomeTaxRateReconciliationUncertainTaxPositionAmount	25633000	USD
CY2021	bku	Effective Income Tax Rate Reconciliation Uncertain Tax Position Percent EffectiveIncomeTaxRateReconciliationUncertainTaxPositionPercent	0.0570
CY2020	bku	Effective Income Tax Rate Reconciliation Uncertain Tax Position Amount EffectiveIncomeTaxRateReconciliationUncertainTaxPositionAmount	3734000	USD
CY2020	bku	Effective Income Tax Rate Reconciliation Uncertain Tax Position Percent EffectiveIncomeTaxRateReconciliationUncertainTaxPositionPercent	0.0150
CY2019	bku	Effective Income Tax Rate Reconciliation Uncertain Tax Position Amount EffectiveIncomeTaxRateReconciliationUncertainTaxPositionAmount	495000	USD
CY2019	bku	Effective Income Tax Rate Reconciliation Uncertain Tax Position Percent EffectiveIncomeTaxRateReconciliationUncertainTaxPositionPercent	0.0012
CY2021	us-gaap	Income Tax Reconciliation Tax Settlements IncomeTaxReconciliationTaxSettlements	-43949000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Tax Settlements EffectiveIncomeTaxRateReconciliationTaxSettlements	-0.0978
CY2020	us-gaap	Income Tax Reconciliation Tax Settlements IncomeTaxReconciliationTaxSettlements	0	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Settlements EffectiveIncomeTaxRateReconciliationTaxSettlements	0
CY2019	us-gaap	Income Tax Reconciliation Tax Settlements IncomeTaxReconciliationTaxSettlements	0	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Settlements EffectiveIncomeTaxRateReconciliationTaxSettlements	0
CY2021	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	618000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.0014
CY2020	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	5183000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.0208
CY2019	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	4548000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.0112
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	34401000	USD
CY2021	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.0766
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	51506000	USD
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.2066
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	90898000	USD
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CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice	63.74
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	737753	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	26.64
CY2020	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	735400	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	26.67
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod	784	shares
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CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	1569	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	15.94
CY2021	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	1569	shares
CY2021	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	15.94
CY2021	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod	0	shares
CY2021	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice	0
CY2021Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	0	shares
CY2021Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	0	shares
CY2021Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	0
CY2021Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	0
CY2021Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	10118369000	USD
CY2021Q4	us-gaap	Liabilities Fair Value Disclosure LiabilitiesFairValueDisclosure	25314000	USD
CY2020Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	9297586000	USD
CY2020Q4	us-gaap	Liabilities Fair Value Disclosure LiabilitiesFairValueDisclosure	44490000	USD
CY2021	us-gaap	Cash Dividends Paid To Parent Company By Consolidated Subsidiaries CashDividendsPaidToParentCompanyByConsolidatedSubsidiaries	312000000	USD
CY2019	us-gaap	Cash Dividends Paid To Parent Company By Consolidated Subsidiaries CashDividendsPaidToParentCompanyByConsolidatedSubsidiaries	305000000	USD
CY2021Q4	us-gaap	Investments Fair Value Disclosure InvestmentsFairValueDisclosure	10064887000	USD
CY2020Q4	us-gaap	Investments Fair Value Disclosure InvestmentsFairValueDisclosure	9177870000	USD
CY2021Q4	us-gaap	Unused Commitments To Extend Credit UnusedCommitmentsToExtendCredit	4491181000	USD
CY2021Q4	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	237873000	USD
CY2021Q3	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	234345000	USD
CY2021Q2	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	241801000	USD
CY2021Q1	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	245429000	USD
CY2021	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	959448000	USD
CY2021Q4	us-gaap	Interest Expense InterestExpense	31858000	USD
CY2021Q3	us-gaap	Interest Expense InterestExpense	39223000	USD
CY2021Q2	us-gaap	Interest Expense InterestExpense	43490000	USD
CY2021Q1	us-gaap	Interest Expense InterestExpense	49189000	USD
CY2021	us-gaap	Interest Expense InterestExpense	163760000	USD
CY2021Q4	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	206015000	USD
CY2021Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	195122000	USD
CY2021Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	198311000	USD
CY2021Q1	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	196240000	USD
CY2021	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	795688000	USD
CY2021Q4	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	246000	USD
CY2021Q3	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-11842000	USD
CY2021Q2	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-27534000	USD
CY2021Q1	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-27989000	USD
CY2021	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-67119000	USD
CY2021Q4	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	205769000	USD
CY2021Q3	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	206964000	USD
CY2021Q2	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	225845000	USD
CY2021Q1	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	224229000	USD
CY2021	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	862807000	USD
CY2021Q4	us-gaap	Noninterest Income NoninterestIncome	45622000	USD
CY2021Q3	us-gaap	Noninterest Income NoninterestIncome	25478000	USD
CY2021Q2	us-gaap	Noninterest Income NoninterestIncome	32757000	USD
CY2021Q1	us-gaap	Noninterest Income NoninterestIncome	30296000	USD
CY2021	us-gaap	Noninterest Income NoninterestIncome	134153000	USD
CY2021Q4	us-gaap	Noninterest Expense NoninterestExpense	187860000	USD
CY2021Q3	us-gaap	Noninterest Expense NoninterestExpense	118042000	USD
CY2021Q2	us-gaap	Noninterest Expense NoninterestExpense	118452000	USD
CY2021Q1	us-gaap	Noninterest Expense NoninterestExpense	123221000	USD
CY2021	us-gaap	Noninterest Expense NoninterestExpense	547575000	USD
CY2021Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	63531000	USD
CY2021Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	114400000	USD
CY2021Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	140150000	USD
CY2021Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	131304000	USD
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	449385000	USD
CY2021Q4	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-61724000	USD
CY2021Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	27459000	USD
CY2021Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	36176000	USD
CY2021Q1	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	32490000	USD
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	34401000	USD
CY2021Q4	us-gaap	Net Income Loss NetIncomeLoss	125255000	USD
CY2021Q3	us-gaap	Net Income Loss NetIncomeLoss	86941000	USD
CY2021Q2	us-gaap	Net Income Loss NetIncomeLoss	103974000	USD
CY2021Q1	us-gaap	Net Income Loss NetIncomeLoss	98814000	USD
CY2021	us-gaap	Net Income Loss NetIncomeLoss	414984000	USD
CY2021Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.42
CY2021Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.94
CY2021Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.12
CY2021Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.06
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	4.52
CY2021Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.41
CY2021Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.94
CY2021Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.11
CY2021Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.06
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	4.52
CY2020Q4	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	251120000	USD
CY2020Q3	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	254572000	USD
CY2020Q2	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	267778000	USD
CY2020Q1	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	294139000	USD
CY2020	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	1067609000	USD
CY2020Q4	us-gaap	Interest Expense InterestExpense	57754000	USD
CY2020Q3	us-gaap	Interest Expense InterestExpense	67093000	USD
CY2020Q2	us-gaap	Interest Expense InterestExpense	77441000	USD
CY2020Q1	us-gaap	Interest Expense InterestExpense	113563000	USD
CY2020	us-gaap	Interest Expense InterestExpense	315851000	USD
CY2020Q4	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	193366000	USD
CY2020Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	187479000	USD
CY2020Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	190337000	USD
CY2020Q1	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	180576000	USD
CY2020	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	751758000	USD
CY2020Q4	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-1643000	USD
CY2020Q3	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	29232000	USD
CY2020Q2	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	25414000	USD
CY2020Q1	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	125428000	USD
CY2020	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	178431000	USD
CY2020Q4	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	195009000	USD
CY2020Q3	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	158247000	USD
CY2020Q2	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	164923000	USD
CY2020Q1	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	55148000	USD
CY2020	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	573327000	USD
CY2020Q4	us-gaap	Noninterest Income NoninterestIncome	35280000	USD
CY2020Q3	us-gaap	Noninterest Income NoninterestIncome	36292000	USD
CY2020Q2	us-gaap	Noninterest Income NoninterestIncome	38351000	USD
CY2020Q1	us-gaap	Noninterest Income NoninterestIncome	23298000	USD
CY2020	us-gaap	Noninterest Income NoninterestIncome	133221000	USD
CY2020Q4	us-gaap	Noninterest Expense NoninterestExpense	123324000	USD
CY2020Q3	us-gaap	Noninterest Expense NoninterestExpense	108627000	USD
CY2020Q2	us-gaap	Noninterest Expense NoninterestExpense	106370000	USD
CY2020Q1	us-gaap	Noninterest Expense NoninterestExpense	118868000	USD
CY2020	us-gaap	Noninterest Expense NoninterestExpense	457189000	USD
CY2020Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	106965000	USD
CY2020Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	85912000	USD
CY2020Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	96904000	USD
CY2020Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	-40422000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	249359000	USD
CY2020Q4	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	21228000	USD
CY2020Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	19353000	USD
CY2020Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	20396000	USD
CY2020Q1	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-9471000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	51506000	USD
CY2020Q4	us-gaap	Net Income Loss NetIncomeLoss	85737000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	66559000	USD
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	76508000	USD
CY2020Q1	us-gaap	Net Income Loss NetIncomeLoss	-30951000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	197853000	USD
CY2020Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.89
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.70
CY2020Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.80
CY2020Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.33
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.06
CY2020Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.89
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.70
CY2020Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.80
CY2020Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.33
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.06
CY2021Q4	us-gaap	Tax Adjustments Settlements And Unusual Provisions TaxAdjustmentsSettlementsAndUnusualProvisions	43900000	USD
CY2021Q4	bku	Notable Items That Impacted Income Before Income Taxes NotableItemsThatImpactedIncomeBeforeIncomeTaxes	40400000	USD
CY2021Q4	bku	Swap Termination Expenses SwapTerminationExpenses	44833000	USD
CY2021Q4	us-gaap	Payments To Employees PaymentsToEmployees	6809000	USD
CY2021Q4	bku	Professional Fees Related To Tax Settlement ProfessionalFeesRelatedToTaxSettlement	4198000	USD
CY2021Q4	us-gaap	Impairment Lessor Asset Under Operating Lease ImpairmentLessorAssetUnderOperatingLease	2813000	USD
CY2021Q4	bku	Notable Items That Impacted Income Before Income Taxes NotableItemsThatImpactedIncomeBeforeIncomeTaxes	40437000	USD

Files In Submission

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$BKU
BankUnited, Inc. Stock $bku

2021 Q4 Form 10-K Financial Statement

#000150400822000009 Filed on February 24, 2022

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$BKU BankUnited, Inc. Stock $bku

2021 Q4 Form 10-K Financial Statement

#000150400822000009 Filed on February 24, 2022

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$BKU
BankUnited, Inc. Stock $bku