$BKU
BankUnited, Inc. Stock $bku

$bku Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-K Financial Statement

#000150400821000007 Filed on February 26, 2021

Income Statement

Concept	2019 Q4	2019 Q3	2019 Q2
Revenue	$309.4M	$323.4M	$327.2M
YoY Change	-25.41%	-9.59%	-6.2%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development		$10.99M	$12.01M
YoY Change		18.7%	38.98%
% of Gross Profit
Depreciation & Amortization	$19.30M	$17.50M	$17.40M
YoY Change	50.78%	-12.94%	10.13%
% of Gross Profit
Operating Expenses		$10.99M	$12.01M
YoY Change		18.7%	38.98%
Operating Profit
YoY Change
Interest Expense	$124.1M	$137.7M	$136.3M
YoY Change	3.64%	30.23%	45.68%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$104.5M	$100.4M	$108.9M
YoY Change	51.23%	-15.42%	-6.93%
Income Tax	$15.07M	$24.18M	$27.43M
% Of Pretax Income	14.42%	24.09%	25.19%
Net Earnings	$89.46M	$76.22M	$81.45M
YoY Change	70.71%	-21.69%	-9.4%
Net Earnings / Revenue	28.91%	23.57%	24.89%
Basic Earnings Per Share	$0.91	$0.78	$0.81
Diluted Earnings Per Share	$0.91	$0.77	$0.81
COMMON SHARES
Basic Shares Outstanding	94.95M shares	93.98M shares	96.28M shares
Diluted Shares Outstanding		94.26M shares	96.62M shares

Balance Sheet

Concept	2019 Q4	2019 Q3	2019 Q2
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$214.7M	$230.2M	$442.8M
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	$58.10M	$697.0M	$708.0M
YoY Change	-11.74%	5.29%	19.8%
Goodwill	$78.00M
YoY Change	0.0%
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	$32.87B	$32.95B	$33.09B
YoY Change	2.2%	4.56%	5.56%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt	$100.0M	$175.0M	$99.00M
YoY Change	-42.86%	0.0%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$100.0M	$175.0M	$99.00M
YoY Change	-42.86%	0.0%
LONG-TERM LIABILITIES
Long-Term Debt	$429.0M	$404.0M	$404.0M
YoY Change	6.45%	0.25%	0.25%
Other Long-Term Liabilities	$486.0M	$575.0M	$468.0M
YoY Change	23.66%	-5.74%	-21.74%
Total Long-Term Liabilities	$915.0M	$979.0M	$872.0M
YoY Change	14.95%	-3.36%	-12.89%
TOTAL LIABILITIES
Total Short-Term Liabilities	$100.0M	$175.0M	$99.00M
Total Long-Term Liabilities	$915.0M	$979.0M	$872.0M
Total Liabilities	$29.89B	$30.04B	$30.22B
YoY Change	2.22%	5.63%	6.99%
SHAREHOLDERS EQUITY
Retained Earnings	$1.928B	$1.859B	$1.803B
YoY Change	13.54%	11.51%	13.27%
Common Stock	$951.0K	$951.0K	$953.0K
YoY Change	-4.04%	-8.29%	-10.26%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$2.981B	$2.909B	$2.868B
YoY Change
Total Liabilities & Shareholders Equity	$32.87B	$32.95B	$33.09B
YoY Change	2.2%	4.56%	5.56%

Cashflow Statement

Concept	2019 Q4	2019 Q3	2019 Q2
OPERATING ACTIVITIES
Net Income	$89.46M	$76.22M	$81.45M
YoY Change	70.71%	-21.69%	-9.4%
Depreciation, Depletion And Amortization	$19.30M	$17.50M	$17.40M
YoY Change	50.78%	-12.94%	10.13%
Cash From Operating Activities	$223.5M	$174.4M	$149.3M
YoY Change	-46.84%	0.23%	62.64%
INVESTING ACTIVITIES
Capital Expenditures	-$25.50M	-$1.200M	-$14.70M
YoY Change	-52.07%	-98.52%	-65.08%
Acquisitions
YoY Change
Other Investing Activities	-$57.50M	-$92.60M	-$274.5M
YoY Change	-94.53%	-67.16%	-39.72%
Cash From Investing Activities	-$83.00M	-$93.70M	-$289.3M
YoY Change	-92.48%	-74.2%	-41.84%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-156.1M	-293.2M	341.3M
YoY Change	-119.85%	-426.87%	-41.68%
NET CHANGE
Cash From Operating Activities	223.5M	174.4M	149.3M
Cash From Investing Activities	-83.00M	-93.70M	-289.3M
Cash From Financing Activities	-156.1M	-293.2M	341.3M
Net Change In Cash	-15.60M	-212.5M	201.3M
YoY Change	-115.23%	113.57%	12.08%
FREE CASH FLOW
Cash From Operating Activities	$223.5M	$174.4M	$149.3M
Capital Expenditures	-$25.50M	-$1.200M	-$14.70M
Free Cash Flow	$249.0M	$175.6M	$164.0M
YoY Change	-47.42%	-31.19%	22.48%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2020	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
CY2020	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2020	dei	Amendment Flag AmendmentFlag	false
CY2020	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2020	dei	Document Type DocumentType	10-K
CY2020	dei	Document Annual Report DocumentAnnualReport	true
CY2020	dei	Document Transition Report DocumentTransitionReport	false
CY2020	dei	Document Period End Date DocumentPeriodEndDate	2020-12-31
CY2020	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2020	dei	Entity File Number EntityFileNumber	001-35039
CY2020	dei	Entity Registrant Name EntityRegistrantName	BankUnited, Inc.
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2020	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	27-0162450
CY2020	dei	Entity Address Address Line1 EntityAddressAddressLine1	14817 Oak Lane
CY2020	dei	Entity Address City Or Town EntityAddressCityOrTown	Miami Lakes
CY2020	dei	Entity Address State Or Province EntityAddressStateOrProvince	FL
CY2020	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	33016
CY2020	dei	City Area Code CityAreaCode	305
CY2020	dei	Local Phone Number LocalPhoneNumber	569-2000
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CY2020	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
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CY2020	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2020	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
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CY2018	us-gaap	Net Income Loss NetIncomeLoss	324866000	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
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-57041000	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
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	4486000	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
CY2018	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-61527000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	-87402000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	-58760000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	3981000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax	-34463000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax	1931000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax	1469000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	-52939000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	-60691000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	2512000	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
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-59015000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	180528000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	276398000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	265851000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	197853000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	313098000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	324866000	USD
CY2020	bku	Amortization Accretion Of Discounts And Premiums AmortizationAccretionOfDiscountsAndPremiums	28246000	USD
CY2020	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	178431000	USD
CY2019	bku	Amortization Accretion Of Discounts And Premiums AmortizationAccretionOfDiscountsAndPremiums	37319000	USD
CY2018	bku	Amortization Accretion Of Discounts And Premiums AmortizationAccretionOfDiscountsAndPremiums	86549000	USD
CY2019	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	8904000	USD
CY2018	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	25925000	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
CY2018	us-gaap	Gain Loss On Sale Of Loans And Leases GainLossOnSaleOfLoansAndLeases	15864000	USD
CY2020	us-gaap	Gain Loss On Investments GainLossOnInvestments	17767000	USD
CY2019	us-gaap	Gain Loss On Investments GainLossOnInvestments	21174000	USD
CY2018	us-gaap	Gain Loss On Investments GainLossOnInvestments	3159000	USD
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	20367000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	23367000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	23137000	USD
CY2020	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	72508000	USD
CY2019	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	72425000	USD
CY2018	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	64268000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-27586000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	24529000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	67778000	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
CY2018	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	268589000	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
CY2018	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	155974000	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
CY2018	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-229109000	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
CY2018	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	82126000	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
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	824252000	USD
CY2020	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	4208597000	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	3896234000	USD
CY2018	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	4138994000	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
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	1533951000	USD
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	1503498000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	2975259000	USD
CY2018	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	1030810000	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
CY2018	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	308126000	USD
CY2020	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	192737000	USD
CY2018	us-gaap	Proceeds From Sale Of Mortgage Servicing Rights Msr ProceedsFromSaleOfMortgageServicingRightsMSR	34573000	USD
CY2019	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	425213000	USD
CY2018	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	307063000	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
CY2018	us-gaap	Payments To Acquire Loans Held For Investment PaymentsToAcquireLoansHeldForInvestment	1308772000	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
CY2018	bku	Payments For Proceeds From Loan Originations Prepayments And Resolutions Net PaymentsForProceedsFromLoanOriginationsPrepaymentsAndResolutionsNet	-404769000	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
CY2018	us-gaap	Proceeds From Sale Of Loans Held For Investment ProceedsFromSaleOfLoansHeldForInvestment	544745000	USD
CY2020	us-gaap	Proceeds From Sale Of Machinery And Equipment ProceedsFromSaleOfMachineryAndEquipment	5310000	USD
CY2019	us-gaap	Proceeds From Sale Of Machinery And Equipment ProceedsFromSaleOfMachineryAndEquipment	19269000	USD
CY2018	us-gaap	Proceeds From Sale Of Machinery And Equipment ProceedsFromSaleOfMachineryAndEquipment	52134000	USD
CY2020	us-gaap	Proceeds From Sale Of Mortgage Servicing Rights Msr ProceedsFromSaleOfMortgageServicingRightsMSR	0	USD
CY2019	us-gaap	Proceeds From Sale Of Mortgage Servicing Rights Msr ProceedsFromSaleOfMortgageServicingRightsMSR	0	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
CY2018	us-gaap	Payments To Acquire Equipment On Lease PaymentsToAcquireEquipmentOnLease	190500000	USD
CY2020	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	22117000	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	39879000	USD
CY2018	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	3184000	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
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2041531000	USD
CY2020	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	3101225000	USD
CY2019	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	920368000	USD
CY2018	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	1595744000	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
CY2018	us-gaap	Increase Decrease In Federal Funds Purchased IncreaseDecreaseInFederalFundsPurchased	-175000000	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
CY2018	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	4647000000	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
CY2018	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	4622000000	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
CY2018	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	0	USD
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	86522000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	84083000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	91305000	USD
CY2020	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	19611000	USD
CY2019	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	5817000	USD
CY2018	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	7727000	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
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	299972000	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
CY2018	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-7424000	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
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	1404770000	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
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	187491000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	214673000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	382073000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	194582000	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
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	382073000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	336991000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	518856000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	387801000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	8637000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	229000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-288267000	USD
CY2020	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	4170000	USD
CY2019	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	3211000	USD
CY2018	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	9709000	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
CY2018	us-gaap	Transfer Of Portfolio Loans And Leases To Held For Sale1 TransferOfPortfolioLoansAndLeasesToHeldForSale1	108503000	USD
CY2020	us-gaap	Transfer Of Loans Held For Sale To Portfolio Loans1 TransferOfLoansHeldForSaleToPortfolioLoans1	0	USD
CY2019	us-gaap	Transfer Of Loans Held For Sale To Portfolio Loans1 TransferOfLoansHeldForSaleToPortfolioLoans1	19716000	USD
CY2018	us-gaap	Transfer Of Loans Held For Sale To Portfolio Loans1 TransferOfLoansHeldForSaleToPortfolioLoans1	0	USD
CY2020	bku	Dividends Declared And Payable DividendsDeclaredAndPayable	22309000	USD
CY2019	bku	Dividends Declared And Payable DividendsDeclaredAndPayable	20775000	USD
CY2018	bku	Dividends Declared And Payable DividendsDeclaredAndPayable	21673000	USD
CY2020	bku	Obligationincurredinacquisitionoflimitedpartnership Obligationincurredinacquisitionoflimitedpartnership	0	USD
CY2019	bku	Obligationincurredinacquisitionoflimitedpartnership Obligationincurredinacquisitionoflimitedpartnership	0	USD
CY2018	bku	Obligationincurredinacquisitionoflimitedpartnership Obligationincurredinacquisitionoflimitedpartnership	4710000	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	3026062000	USD
CY2018Q1	us-gaap	Stockholders Equity StockholdersEquity	3026062000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	265851000	USD
CY2018	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	89923000	USD
CY2018	us-gaap	Stock Issued During Period Value Share Based Compensation Gross StockIssuedDuringPeriodValueShareBasedCompensationGross	20647000	USD
CY2018	us-gaap	Stock Issued During Period Value Share Based Compensation Forfeited StockIssuedDuringPeriodValueShareBasedCompensationForfeited	6559000	USD
CY2018	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	7727000	USD
CY2018	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	299972000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	2923833000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	276398000	USD
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
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
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
CY2020Q4	us-gaap	Assets Assets	35000000000.0	USD
CY2020	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.
CY2020	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<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%">Reclassifications</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%">Certain amounts presented for prior periods have been reclassified to conform to the current period presentation.</span></div>
CY2020	us-gaap	Description Of New Accounting Pronouncements Not Yet Adopted DescriptionOfNewAccountingPronouncementsNotYetAdopted	<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 Pronouncements Not Yet Adopted</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%">ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes. This ASU simplifies the accounting for income taxes by removing certain exceptions stipulated in ASC 740 and making some other targeted changes to the accounting for income taxes. The Company adopted this ASU on January 1, 2021 with no material impact on the Company’s consolidated financial position, results of operations, and cash flows.</span></div>
CY2020	us-gaap	Net Income Loss NetIncomeLoss	197853000	USD
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	103744871	shares
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.06
CY2019	us-gaap	Net Income Loss NetIncomeLoss	313098000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	324866000	USD
CY2020	us-gaap	Participating Securities Distributed And Undistributed Earnings Loss Basic ParticipatingSecuritiesDistributedAndUndistributedEarningsLossBasic	8882000	USD
CY2019	us-gaap	Participating Securities Distributed And Undistributed Earnings Loss Basic ParticipatingSecuritiesDistributedAndUndistributedEarningsLossBasic	13371000	USD
CY2018	us-gaap	Participating Securities Distributed And Undistributed Earnings Loss Basic ParticipatingSecuritiesDistributedAndUndistributedEarningsLossBasic	13047000	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
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	311819000	USD
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
CY2018	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	104916865	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
CY2018	us-gaap	Weighted Average Number Of Shares Common Stock Subject To Repurchase Or Cancellation WeightedAverageNumberOfSharesCommonStockSubjectToRepurchaseOrCancellation	1171994	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
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.14
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.01
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	95656905	shares
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
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	311819000	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
CY2018	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	195000	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
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	311624000	USD
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
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	103744871	shares
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
CY2018	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	332505	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	91730864	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	104077376	shares
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.06
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.13
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.99
CY2020Q4	bku	Dividend Equivalent Rights DividendEquivalentRights	3023314	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
CY2018	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1463607	shares
CY2020Q4	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	8976774000	USD
CY2020Q4	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	117076000	USD
CY2020Q4	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	31441000	USD
CY2020Q4	us-gaap	Available For Sale Securities AvailableForSaleSecurities	9062409000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale And Held To Maturity DebtSecuritiesAvailableForSaleAndHeldToMaturity	8986774000	USD
CY2020Q4	us-gaap	Available For Sale Securities And Held To Maturity Securities AvailableForSaleSecuritiesAndHeldToMaturitySecurities	9072409000	USD
CY2020Q4	us-gaap	Investments Investments	9176683000	USD
CY2019Q4	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	7660319000	USD
CY2019Q4	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	59954000	USD
CY2019Q4	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	21608000	USD
CY2019Q4	us-gaap	Available For Sale Securities AvailableForSaleSecurities	7698665000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale And Held To Maturity DebtSecuritiesAvailableForSaleAndHeldToMaturity	7670319000	USD
CY2019Q4	us-gaap	Available For Sale Securities And Held To Maturity Securities AvailableForSaleSecuritiesAndHeldToMaturitySecurities	7708665000	USD
CY2019Q4	us-gaap	Investments Investments	7769237000	USD
CY2020Q4	bku	Number Of Held To Maturity Securities NumberOfHeldToMaturitySecurities	1
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	913305000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	922531000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	5415656000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	5441360000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	2137170000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	2180434000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	510643000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	518084000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	8976774000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	9062409000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Restricted DebtSecuritiesAvailableForSaleRestricted	4100000000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Restricted DebtSecuritiesAvailableForSaleRestricted	2400000000	USD
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	1503498000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	2975259000	USD
CY2018	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	1030810000	USD
CY2020	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	14441000	USD
CY2019	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	21961000	USD
CY2018	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	8617000	USD
CY2020	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	440000	USD
CY2019	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	3424000	USD
CY2018	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	2514000	USD
CY2020	us-gaap	Availableforsale Securities Gross Realized Gain Loss Excluding Other Than Temporary Impairments AvailableforsaleSecuritiesGrossRealizedGainLossExcludingOtherThanTemporaryImpairments	14001000	USD
CY2019	us-gaap	Availableforsale Securities Gross Realized Gain Loss Excluding Other Than Temporary Impairments AvailableforsaleSecuritiesGrossRealizedGainLossExcludingOtherThanTemporaryImpairments	18537000	USD
CY2018	us-gaap	Availableforsale Securities Gross Realized Gain Loss Excluding Other Than Temporary Impairments AvailableforsaleSecuritiesGrossRealizedGainLossExcludingOtherThanTemporaryImpairments	6103000	USD
CY2020	us-gaap	Unrealized Gain Loss On Securities UnrealizedGainLossOnSecurities	-3766000	USD
CY2019	us-gaap	Unrealized Gain Loss On Securities UnrealizedGainLossOnSecurities	-2637000	USD
CY2018	us-gaap	Unrealized Gain Loss On Securities UnrealizedGainLossOnSecurities	2944000	USD
CY2020	us-gaap	Gain Loss On Investments GainLossOnInvestments	17767000	USD
CY2019	us-gaap	Gain Loss On Investments GainLossOnInvestments	21174000	USD
CY2018	us-gaap	Gain Loss On Investments GainLossOnInvestments	3159000	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	2165618000	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	16966000	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	1158153000	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	14475000	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue	3323771000	USD
CY2020Q4	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	31441000	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	1922326000	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	9848000	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	1205877000	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	11760000	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue	3128203000	USD
CY2019Q4	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	21608000	USD
CY2020Q4	us-gaap	Availableforsale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions1 AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions1	148	security
CY2020Q4	bku	Number Of Securities Amount Of Impairment Insignificant NumberOfSecuritiesAmountOfImpairmentInsignificant	24	security
CY2020Q4	bku	Availableforsalesecurities Gross Unrealized Loss Considered Insignificantfor Otti Analysis AvailableforsalesecuritiesGrossUnrealizedLossConsideredInsignificantforOTTIAnalysis	300000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	23866042000	USD
CY2020Q4	bku	Percent Of Total Loans PercentOfTotalLoans	1.000
CY2019Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	23154988000	USD
CY2019Q4	bku	Percent Of Total Loans PercentOfTotalLoans	1.000
CY2020Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	257323000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	108671000	USD
CY2020	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	8610000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	23608719000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	23046317000	USD
CY2020Q4	us-gaap	Financing Receivable Deferred Income FinancingReceivableDeferredIncome	39000000	USD
CY2019Q4	us-gaap	Financing Receivable Deferred Income FinancingReceivableDeferredIncome	50000000	USD
CY2020	us-gaap	Financing Receivable Purchased With Credit Deterioration Discount Premium FinancingReceivablePurchasedWithCreditDeteriorationDiscountPremium	-115000000	USD
CY2020Q4	us-gaap	Pledged Financial Instruments Not Separately Reported Loans Receivable Pledged For Federal Home Loan Bank Debt PledgedFinancialInstrumentsNotSeparatelyReportedLoansReceivablePledgedForFederalHomeLoanBankDebt	9600000000	USD
CY2019Q4	us-gaap	Pledged Financial Instruments Not Separately Reported Loans Receivable Pledged For Federal Home Loan Bank Debt PledgedFinancialInstrumentsNotSeparatelyReportedLoansReceivablePledgedForFederalHomeLoanBankDebt	10200000000	USD
CY2020Q4	us-gaap	Interest Receivable InterestReceivable	99000000	USD
CY2019Q4	us-gaap	Interest Receivable InterestReceivable	83000000	USD
CY2020	us-gaap	Financing Receivable Nonaccrual Interest Income FinancingReceivableNonaccrualInterestIncome	3500000	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
CY2017Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	144795000	USD
CY2020	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	69602000	USD
CY2019	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	17541000	USD
CY2018	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	67084000	USD
CY2019	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	7377000	USD
CY2018	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	6295000	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
CY2020	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	14700000	USD
CY2020Q4	bku	Sales On Commercial Loans SalesOnCommercialLoans	49600000	USD
CY2020	us-gaap	Provision For Other Credit Losses ProvisionForOtherCreditLosses	364000	USD
CY2020	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	178431000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	22814034000	USD
CY2020Q4	us-gaap	Financing Receivable Before Allowance For Credit Loss And Fee FinancingReceivableBeforeAllowanceForCreditLossAndFee	23866042000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	22359032000	USD
CY2019Q4	us-gaap	Financing Receivable Before Allowance For Credit Loss And Fee FinancingReceivableBeforeAllowanceForCreditLossAndFee	23154988000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	562000000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	531000000	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
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
CY2019Q4	us-gaap	Loans And Leases Receivable Impaired Nonperforming Nonaccrual Of Interest LoansAndLeasesReceivableImpairedNonperformingNonaccrualOfInterest	204788000	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
CY2020Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	156097000	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
CY2018	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	47
CY2018	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	20116000	USD
CY2018	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	21
CY2018	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	5655000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	108671000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	20490000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	88181000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	23154988000	USD
CY2019Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	244905000	USD
CY2019Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	22743323000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	244905000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	245029000	USD
CY2019	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	152630000	USD
CY2018	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	176341000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	84874000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	92553000	USD
CY2020Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	29119000	USD
CY2019Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	31587000	USD
CY2020Q4	bku	Total Rightof Use Asset TotalRightofUseAsset	113993000	USD
CY2019Q4	bku	Total Rightof Use Asset TotalRightofUseAsset	124140000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	32563000	USD
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	34248000	USD
CY2020Q4	bku	Total Lease Liabilities TotalLeaseLiabilities	126241000	USD
CY2019Q4	bku	Total Lease Liabilities TotalLeaseLiabilities	136512000	USD
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P7Y2M12D
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P7Y8M12D
CY2020Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P12Y8M12D
CY2019Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P13Y7M6D
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.031
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.033
CY2020Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.029
CY2019Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.029
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	20112000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	20284000	USD
CY2020	us-gaap	Operating Lease Impairment Loss OperatingLeaseImpairmentLoss	108000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	20589000	USD
CY2019	us-gaap	Operating Lease Impairment Loss OperatingLeaseImpairmentLoss	1278000	USD
CY2020	us-gaap	Lease Cost LeaseCost	20220000	USD
CY2019	us-gaap	Lease Cost LeaseCost	21562000	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
CY2020	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	921000	USD
CY2019	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	1002000	USD
CY2020	bku	Totalfinanceleasecost Totalfinanceleasecost	3762000	USD
CY2019	bku	Totalfinanceleasecost Totalfinanceleasecost	2644000	USD
CY2020	us-gaap	Variable Lease Cost VariableLeaseCost	4761000	USD
CY2019	us-gaap	Variable Lease Cost VariableLeaseCost	3950000	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
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	20795000	USD
CY2020	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	2980000	USD
CY2019	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	2529000	USD
CY2020	bku	Totalcashpaidforamountsincludedinthemeasurementofleaseliabilities Totalcashpaidforamountsincludedinthemeasurementofleaseliabilities	24490000	USD
CY2019	bku	Totalcashpaidforamountsincludedinthemeasurementofleaseliabilities Totalcashpaidforamountsincludedinthemeasurementofleaseliabilities	24326000	USD
CY2020	bku	Operatingleaseliabilitiesrecognizedfromobtaining Ro Uassets OperatingleaseliabilitiesrecognizedfromobtainingROUassets	9647000	USD
CY2019	bku	Operatingleaseliabilitiesrecognizedfromobtaining Ro Uassets OperatingleaseliabilitiesrecognizedfromobtainingROUassets	15778000	USD
CY2020	bku	Financeleaseliabilitiesrecognizedfromobtaining Ro Uassets FinanceleaseliabilitiesrecognizedfromobtainingROUassets	373000	USD
CY2019	bku	Financeleaseliabilitiesrecognizedfromobtaining Ro Uassets FinanceleaseliabilitiesrecognizedfromobtainingROUassets	27415000	USD
CY2020	bku	Totalleaseliabilitiesrecognizedfromobtaining Ro Uassets TotalleaseliabilitiesrecognizedfromobtainingROUassets	10020000	USD
CY2019	bku	Totalleaseliabilitiesrecognizedfromobtaining Ro Uassets TotalleaseliabilitiesrecognizedfromobtainingROUassets	147257000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	19949000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	3213000	USD
CY2020Q4	bku	Total Lease Liability Payments Due Next Twelve Months TotalLeaseLiabilityPaymentsDueNextTwelveMonths	23162000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	16879000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	2650000	USD
CY2020Q4	bku	Total Lease Liability Payments Due Year Two TotalLeaseLiabilityPaymentsDueYearTwo	19529000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	14431000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	2666000	USD
CY2020Q4	bku	Total Lease Liability Payments Due Year Three TotalLeaseLiabilityPaymentsDueYearThree	17097000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	12658000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	2701000	USD
CY2020Q4	bku	Total Lease Liability Payments Due Year Four TotalLeaseLiabilityPaymentsDueYearFour	15359000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	9966000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	2774000	USD
CY2020Q4	bku	Total Lease Liability Payments Due Year Five TotalLeaseLiabilityPaymentsDueYearFive	12740000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	31072000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due After Year Five FinanceLeaseLiabilityPaymentsDueAfterYearFive	25223000	USD
CY2020Q4	bku	Total Lease Liability Payments Due After Year Five TotalLeaseLiabilityPaymentsDueAfterYearFive	56295000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	104955000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	39227000	USD
CY2020Q4	bku	Total Lease Liability Payments Due TotalLeaseLiabilityPaymentsDue	144182000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	11277000	USD
CY2020Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	6664000	USD
CY2020Q4	bku	Total Lease Liability Undiscounted Excess Amount TotalLeaseLiabilityUndiscountedExcessAmount	17941000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	32563000	USD
CY2020Q4	bku	Total Lease Liabilities TotalLeaseLiabilities	126241000	USD
CY2020Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable Payments To Be Received SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceived	727401000	USD
CY2019Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable Payments To Be Received SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceived	804103000	USD
CY2020Q4	us-gaap	Direct Financing Lease Unguaranteed Residual Asset DirectFinancingLeaseUnguaranteedResidualAsset	5599000	USD
CY2019Q4	us-gaap	Direct Financing Lease Unguaranteed Residual Asset DirectFinancingLeaseUnguaranteedResidualAsset	8471000	USD
CY2020Q4	bku	Salestypeordirectfinancingleasegrossinvestment Salestypeordirectfinancingleasegrossinvestment	733000000	USD
CY2019Q4	bku	Salestypeordirectfinancingleasegrossinvestment Salestypeordirectfinancingleasegrossinvestment	812574000	USD
CY2020Q4	us-gaap	Direct Financing Lease Deferred Selling Profit DirectFinancingLeaseDeferredSellingProfit	66443000	USD
CY2019Q4	us-gaap	Direct Financing Lease Deferred Selling Profit DirectFinancingLeaseDeferredSellingProfit	84175000	USD
CY2020Q4	us-gaap	Capital Leases Net Investment In Direct Financing Leases Initial Direct Costs CapitalLeasesNetInvestmentInDirectFinancingLeasesInitialDirectCosts	3306000	USD
CY2019Q4	us-gaap	Capital Leases Net Investment In Direct Financing Leases Initial Direct Costs CapitalLeasesNetInvestmentInDirectFinancingLeasesInitialDirectCosts	4453000	USD
CY2020Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable SalesTypeAndDirectFinancingLeasesLeaseReceivable	669863000	USD
CY2019Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable SalesTypeAndDirectFinancingLeasesLeaseReceivable	732852000	USD
CY2020Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable Payments To Be Received Next Twelve Months SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedNextTwelveMonths	192486000	USD
CY2020Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable Payments To Be Received Two Years SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedTwoYears	140263000	USD
CY2020Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable Payments To Be Received Three Years SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedThreeYears	109887000	USD
CY2020Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable Payments To Be Received Four Years SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedFourYears	66254000	USD
CY2020Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable Payments To Be Received Five Years SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedFiveYears	49463000	USD
CY2020Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable Payments To Be Received Thereafter SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedThereafter	169048000	USD
CY2020Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable Payments To Be Received SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceived	727401000	USD
CY2020Q4	us-gaap	Property Subject To Or Available For Operating Lease Gross PropertySubjectToOrAvailableForOperatingLeaseGross	844953000	USD
CY2019Q4	us-gaap	Property Subject To Or Available For Operating Lease Gross PropertySubjectToOrAvailableForOperatingLeaseGross	844015000	USD
CY2020Q4	us-gaap	Property Subject To Or Available For Operating Lease Accumulated Depreciation PropertySubjectToOrAvailableForOperatingLeaseAccumulatedDepreciation	181436000	USD
CY2019Q4	us-gaap	Property Subject To Or Available For Operating Lease Accumulated Depreciation PropertySubjectToOrAvailableForOperatingLeaseAccumulatedDepreciation	145862000	USD
CY2020Q4	us-gaap	Property Subject To Or Available For Operating Lease Net PropertySubjectToOrAvailableForOperatingLeaseNet	663517000	USD
CY2019Q4	us-gaap	Property Subject To Or Available For Operating Lease Net PropertySubjectToOrAvailableForOperatingLeaseNet	698153000	USD
CY2020	us-gaap	Asset Impairment Charges AssetImpairmentCharges	700000	USD
CY2019	us-gaap	Asset Impairment Charges AssetImpairmentCharges	1900000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Receivable Current OperatingLeasesFutureMinimumPaymentsReceivableCurrent	49246000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Receivable In Two Years OperatingLeasesFutureMinimumPaymentsReceivableInTwoYears	44525000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Receivable In Three Years OperatingLeasesFutureMinimumPaymentsReceivableInThreeYears	38263000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Receivable In Four Years OperatingLeasesFutureMinimumPaymentsReceivableInFourYears	33856000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Receivable In Five Years OperatingLeasesFutureMinimumPaymentsReceivableInFiveYears	27612000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Receivable Thereafter OperatingLeasesFutureMinimumPaymentsReceivableThereafter	54845000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Receivable OperatingLeasesFutureMinimumPaymentsReceivable	248347000	USD
CY2020	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	59112000	USD
CY2019	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	66631000	USD
CY2020	us-gaap	Direct Financing Lease Lease Income DirectFinancingLeaseLeaseIncome	20995000	USD
CY2019	us-gaap	Direct Financing Lease Lease Income DirectFinancingLeaseLeaseIncome	21865000	USD
CY2020	us-gaap	Lease Income LeaseIncome	80107000	USD
CY2019	us-gaap	Lease Income LeaseIncome	88496000	USD
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
CY2018	bku	Noninterest Bearing Deposit Liabilities Domestic Average Balance NoninterestBearingDepositLiabilitiesDomesticAverageBalance	3389191000	USD
CY2018Q4	bku	Weighted Average Rate Non Interest Bearing Domestic Deposit WeightedAverageRateNonInterestBearingDomesticDeposit	0
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
CY2018	bku	Interest Bearing Deposit Liabilities Domestic Average Balance InterestBearingDepositLiabilitiesDomesticAverageBalance	1627828000	USD
CY2018Q4	bku	Weighted Average Rate Interest Bearing Domestic Deposit WeightedAverageRateInterestBearingDomesticDeposit	0.0113
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
CY2018	bku	Savings And Money Market Average Balance SavingsAndMoneyMarketAverageBalance	10634970000	USD
CY2018Q4	bku	Weighted Average Rate Domestic Deposit Savings And Money Market WeightedAverageRateDomesticDepositSavingsAndMoneyMarket	0.0138
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
CY2018	bku	Time Deposits Average Balance TimeDepositsAverageBalance	6617006000	USD
CY2018Q4	us-gaap	Weighted Average Rate Domestic Deposit Time Deposits WeightedAverageRateDomesticDepositTimeDeposits	0.0181
CY2020	bku	Deposits Average Balance DepositsAverageBalance	25805093000	USD
CY2020Q4	bku	Us Gaap Weighted Average Rate Domestic Deposits UsGaap_WeightedAverageRateDomesticDeposits	0.0077
CY2019	bku	Deposits Average Balance DepositsAverageBalance	23626733000	USD
CY2019Q4	bku	Us Gaap Weighted Average Rate Domestic Deposits UsGaap_WeightedAverageRateDomesticDeposits	0.0163
CY2018	bku	Deposits Average Balance DepositsAverageBalance	22268995000	USD
CY2018Q4	bku	Us Gaap Weighted Average Rate Domestic Deposits UsGaap_WeightedAverageRateDomesticDeposits	0.0128
CY2020Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	1100000000	USD
CY2019Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	1900000000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	4655878000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	110183000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	24368000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	1302000	USD
CY2020Q4	us-gaap	Time Deposit Maturities After Year Five TimeDepositMaturitiesAfterYearFive	15468000	USD
CY2020Q4	us-gaap	Time Deposits TimeDeposits	4807199000	USD
CY2020Q4	bku	Publicfundsdepositsincludedindeposits Publicfundsdepositsincludedindeposits	2500000000	USD
CY2020Q4	us-gaap	Interest Bearing Domestic Deposit Brokered InterestBearingDomesticDepositBrokered	4000000000.0	USD
CY2020Q4	bku	Carrying Value Of Investment Securities Available For Sale Pledged As Security For Time Deposits Issued To Subsidiary And Other Public Funds CarryingValueOfInvestmentSecuritiesAvailableForSalePledgedAsSecurityForTimeDepositsIssuedToSubsidiaryAndOtherPublicFunds	952000000	USD
CY2020	bku	Schedule Of Interest Expense On Deposits ScheduleOfInterestExpenseOnDeposits	<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%">Interest expense on deposits for the years ended December 31, 2020, 2019 and 2018 was as follows (in thousands):</span></div><div style="margin-bottom:5pt;margin-top:5pt"><table style="border-collapse:collapse;display:inline-table;vertical-align:top;width:100.000%"><tr><td style="width:1.0%"/><td style="width:59.280%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.619%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.530%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.619%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.530%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.622%"/><td style="width:0.1%"/></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:100%"> </span></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2020</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2019</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2018</span></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Interest bearing demand</span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">19,445 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">25,054 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">18,391 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Savings and money market</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">85,572 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">197,942 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">146,324 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Time</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">94,963 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">162,184 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">119,848 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;border-bottom:3pt double #000;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000;border-top:1pt solid #000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">199,980 </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">385,180 </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">284,563 </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr></table></div>
CY2020	us-gaap	Interest Expense Demand Deposit Accounts InterestExpenseDemandDepositAccounts	19445000	USD
CY2019	us-gaap	Interest Expense Demand Deposit Accounts InterestExpenseDemandDepositAccounts	25054000	USD
CY2018	us-gaap	Interest Expense Demand Deposit Accounts InterestExpenseDemandDepositAccounts	18391000	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
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CY2020Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Average Interest Rate One To Two Years From Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateOneToTwoYearsFromBalanceSheetDate	0.0041
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CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	63083000	USD
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CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	3570000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	10431000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeTax	47290000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	11676000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	35614000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax	-116168000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	-28766000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	-87402000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax	-46259000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesTax	-11796000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax	-34463000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Before Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesBeforeTax	-69909000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax	-16970000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	-52939000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-22619000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-5294000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-17325000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	51178000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	13562000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	37616000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	18537000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	4912000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	13625000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeTax	32641000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	8650000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	23991000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax	-79945000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	-21185000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	-58760000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax	2627000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesTax	696000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax	1931000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Before Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesBeforeTax	-82572000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax	-21881000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	-60691000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-49931000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-13231000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-36700000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-77607000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-20566000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-57041000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	6103000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	1617000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	4486000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeTax	-83710000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	-22183000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-61527000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax	5416000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	1435000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	3981000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax	1999000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesTax	530000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax	1469000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Before Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesBeforeTax	3417000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax	905000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	2512000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-80293000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-21278000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-59015000	USD
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	20514000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	23476000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	23240000	USD
CY2020	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	4854000	USD
CY2019	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	4068000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	5783000	USD
CY2020	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	15660000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	19408000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	17457000	USD
CY2020	bku	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Date Of Grant Closing Price Minimum ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodDateOfGrantClosingPriceMinimum	13.99
CY2020	bku	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Date Of Grant Closing Price Maximum ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodDateOfGrantClosingPriceMaximum	30.90
CY2019	bku	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Date Of Grant Closing Price Minimum ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodDateOfGrantClosingPriceMinimum	31.07
CY2019	bku	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Date Of Grant Closing Price Maximum ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodDateOfGrantClosingPriceMaximum	36.65
CY2018	bku	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Date Of Grant Closing Price Minimum ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodDateOfGrantClosingPriceMinimum	33.44
CY2018	bku	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Date Of Grant Closing Price Maximum ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodDateOfGrantClosingPriceMaximum	42.80
CY2020	bku	Sharebased Compensation Arrangement By Sharebased Payment Award Equity Instruments Other Than Options Aggregate Grant Date Fair Value Vested SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateGrantDateFairValueVested	18654000	USD
CY2019	bku	Sharebased Compensation Arrangement By Sharebased Payment Award Equity Instruments Other Than Options Aggregate Grant Date Fair Value Vested SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateGrantDateFairValueVested	21064000	USD
CY2018	bku	Sharebased Compensation Arrangement By Sharebased Payment Award Equity Instruments Other Than Options Aggregate Grant Date Fair Value Vested SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateGrantDateFairValueVested	18451000	USD
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	1270688	shares
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	26.93
CY2018	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	291689	shares
CY2018	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	26.49
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod	14159	shares
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice	63.74
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	964840	shares
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	26.53
CY2019	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	225127	shares
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	25.84
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod	1960	shares
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
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice	22.18
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	1569	shares
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
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	15.94
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P0Y3M18D
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	2300000	USD
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	4600000	USD
CY2020	us-gaap	Employee Service Share Based Compensation Tax Benefit From Exercise Of Stock Options EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions	600000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Exercise Of Stock Options EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions	1100000	USD
CY2020Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	9297586000	USD
CY2020Q4	us-gaap	Liabilities Fair Value Disclosure LiabilitiesFairValueDisclosure	44490000	USD
CY2019Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	7810900000	USD
CY2019Q4	us-gaap	Liabilities Fair Value Disclosure LiabilitiesFairValueDisclosure	19029000	USD
CY2020Q4	us-gaap	Investments Fair Value Disclosure InvestmentsFairValueDisclosure	9177870000	USD
CY2019Q4	us-gaap	Investments Fair Value Disclosure InvestmentsFairValueDisclosure	7769949000	USD
CY2020Q4	us-gaap	Unused Commitments To Extend Credit UnusedCommitmentsToExtendCredit	4133006000	USD
CY2019	us-gaap	Cash Dividends Paid To Parent Company By Consolidated Subsidiaries CashDividendsPaidToParentCompanyByConsolidatedSubsidiaries	305000000	USD
CY2018	us-gaap	Cash Dividends Paid To Parent Company By Consolidated Subsidiaries CashDividendsPaidToParentCompanyByConsolidatedSubsidiaries	420000000	USD
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
CY2020	us-gaap	Noninterest Income NoninterestIncome	133221000	USD
CY2019Q1	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	321829000	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 And Lease Losses ProvisionForLoanAndLeaseLosses	-1643000	USD
CY2020Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	29232000	USD
CY2020Q2	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	25414000	USD
CY2020Q1	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	125428000	USD
CY2020	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	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
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	Earnings Per Share Basic EarningsPerShareBasic	0.80
CY2020Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.33
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
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
CY2019Q4	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	309410000	USD
CY2019Q3	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	323402000	USD
CY2019Q2	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	327229000	USD
CY2019	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	1281870000	USD
CY2019Q4	us-gaap	Interest Expense InterestExpense	124099000	USD
CY2019Q3	us-gaap	Interest Expense InterestExpense	137712000	USD
CY2019Q2	us-gaap	Interest Expense InterestExpense	136346000	USD
CY2019Q1	us-gaap	Interest Expense InterestExpense	130928000	USD
CY2019	us-gaap	Interest Expense InterestExpense	529085000	USD
CY2019Q4	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	185311000	USD
CY2019Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	185690000	USD
CY2019Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	190883000	USD
CY2019Q1	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	190901000	USD
CY2019	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	752785000	USD
CY2019Q4	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	-469000	USD
CY2019Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	1839000	USD
CY2019Q2	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	-2747000	USD
CY2019Q1	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	10281000	USD
CY2019	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	8904000	USD
CY2019Q4	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	185780000	USD
CY2019Q3	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	183851000	USD
CY2019	us-gaap	Noninterest Expense NoninterestExpense	487089000	USD
CY2019Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	104528000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	100401000	USD
CY2019Q2	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	193630000	USD
CY2019Q1	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	180620000	USD
CY2019	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	743881000	USD
CY2019Q4	us-gaap	Noninterest Income NoninterestIncome	37756000	USD
CY2019Q3	us-gaap	Noninterest Income NoninterestIncome	37856000	USD
CY2019Q2	us-gaap	Noninterest Income NoninterestIncome	35337000	USD
CY2019Q1	us-gaap	Noninterest Income NoninterestIncome	36255000	USD
CY2019	us-gaap	Noninterest Income NoninterestIncome	147204000	USD
CY2019Q4	us-gaap	Noninterest Expense NoninterestExpense	119008000	USD
CY2019Q3	us-gaap	Noninterest Expense NoninterestExpense	121306000	USD
CY2019Q2	us-gaap	Noninterest Expense NoninterestExpense	120085000	USD
CY2019Q1	us-gaap	Noninterest Expense NoninterestExpense	126690000	USD
CY2019Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	108882000	USD
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.14
CY2019Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.91
CY2019Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	90185000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	403996000	USD
CY2019Q4	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	15072000	USD
CY2019Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	24182000	USD
CY2019Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	27431000	USD
CY2019Q1	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	24213000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	90898000	USD
CY2019Q4	us-gaap	Net Income Loss NetIncomeLoss	89456000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	76219000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	81451000	USD
CY2019Q1	us-gaap	Net Income Loss NetIncomeLoss	65972000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	313098000	USD
CY2019Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.91
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.78
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.81
CY2019Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.65
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.77
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.81
CY2019Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.65
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.13

Files In Submission

Name	View Source	Status
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$BKU
BankUnited, Inc. Stock $bku

2019 Q4 Form 10-K Financial Statement

#000150400821000007 Filed on February 26, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$BKU BankUnited, Inc. Stock $bku

2019 Q4 Form 10-K Financial Statement

#000150400821000007 Filed on February 26, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$BKU
BankUnited, Inc. Stock $bku