$MBWM
Mercantile Bank Corp Stock $mbwm

$mbwm Overview Financials Valuation SEC Filings Company Website

2023 Q1 Form 10-K Financial Statement

#000143774923005339 Filed on March 03, 2023

Income Statement

Concept	2023 Q1	2022 Q4	2022
Revenue	$60.49M		$181.8M
YoY Change	68.57%		26.72%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$1.500M	$3.090M	$6.000M
YoY Change	-6.25%	-11.21%	3.45%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense	$12.10M		$23.60M
YoY Change	142.17%		21.42%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$26.14M	$26.87M	$75.79M
YoY Change	82.51%	76.55%	2.81%
Income Tax	$5.162M	$5.068M	$14.73M
% Of Pretax Income	19.75%	18.86%	19.43%
Net Earnings	$20.97M	$21.80M	$61.06M
YoY Change	82.51%	87.33%	3.46%
Net Earnings / Revenue	34.68%		33.58%
Basic Earnings Per Share	$1.31		$3.85
Diluted Earnings Per Share	$1.31	$1.372M	$3.850M
COMMON SHARES
Basic Shares Outstanding	16.00M	15.87M	15.86M
Diluted Shares Outstanding	16.00M		15.86M

Balance Sheet

Concept	2023 Q1	2022 Q4	2022
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$57.94M	$96.77M
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	$51.51M	$51.48M	$51.48M
YoY Change	-8.15%	-10.16%	-10.16%
Goodwill	$49.47M	$49.47M
YoY Change	0.0%	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	$4.896B	$4.873B	$4.873B
YoY Change	-5.41%	-7.32%	-7.32%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$70.07M	$78.21M	$78.21M
YoY Change	88.36%	217.93%	217.93%
Accrued Expenses	$3.900M	$3.500M	$3.500M
YoY Change	50.0%
Deferred Revenue
YoY Change
Short-Term Debt	$244.7M	$194.3M	$194.3M
YoY Change	19.77%	-1.6%	-1.6%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$314.7M	$78.21M	$78.21M
YoY Change	690.78%	217.93%	217.93%
LONG-TERM LIABILITIES
Long-Term Debt	$137.8M	$137.6M	$137.6M
YoY Change	0.73%	12.87%	12.87%
Other Long-Term Liabilities
YoY Change
Total Long-Term Liabilities	$137.8M	$137.6M	$137.6M
YoY Change	0.73%	12.87%	12.87%
TOTAL LIABILITIES
Total Short-Term Liabilities	$314.7M	$78.21M	$78.21M
Total Long-Term Liabilities	$137.8M	$137.6M	$137.6M
Total Liabilities	$4.429B	$4.431B	$4.431B
YoY Change	-6.56%	-7.71%	-7.71%
SHAREHOLDERS EQUITY
Retained Earnings	$232.1M	$216.3M
YoY Change	27.87%	23.94%
Common Stock	$291.5M	$290.4M
YoY Change	1.63%	1.64%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$467.4M	$441.4M	$441.4M
YoY Change
Total Liabilities & Shareholders Equity	$4.896B	$4.873B	$4.873B
YoY Change	-5.41%	-7.32%	-7.32%

Cashflow Statement

Concept	2023 Q1	2022 Q4	2022
OPERATING ACTIVITIES
Net Income	$20.97M	$21.80M	$61.06M
YoY Change	82.51%	87.33%	3.46%
Depreciation, Depletion And Amortization	$1.500M	$3.090M	$6.000M
YoY Change	-6.25%	-11.21%	3.45%
Cash From Operating Activities	$18.07M	$37.07M	$119.9M
YoY Change	-35.22%	-18.35%	85.62%
INVESTING ACTIVITIES
Capital Expenditures	$2.508M	$851.0K	$3.017M
YoY Change	-855.42%	-163.04%	-153.88%
Acquisitions
YoY Change
Other Investing Activities	-$54.63M	-$51.15M	-$552.0M
YoY Change	-63.77%	-71.22%	12.67%
Cash From Investing Activities	-$57.14M	-$52.00M	-$555.0M
YoY Change	-62.19%	-70.96%	12.01%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	$237.0K	-172.3M	-$443.3M
YoY Change	-100.29%	-160.79%	-156.82%
NET CHANGE
Cash From Operating Activities	$18.07M	37.07M	$119.9M
Cash From Investing Activities	-$57.14M	-52.00M	-$555.0M
Cash From Financing Activities	$237.0K	-172.3M	-$443.3M
Net Change In Cash	-$38.83M	-187.2M	-$878.4M
YoY Change	-81.05%	-224.99%	-351.58%
FREE CASH FLOW
Cash From Operating Activities	$18.07M	$37.07M	$119.9M
Capital Expenditures	$2.508M	$851.0K	$3.017M
Free Cash Flow	$15.56M	$36.22M	$116.8M
YoY Change	-44.87%	-22.53%	66.51%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2021	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21	pure
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21	pure
CY2021Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0	usd
CY2021Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	0	usd
CY2021	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	0
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	0
CY2022	mbwm	Term Debt Secured By Real Estate Balloon Payment Period TermDebtSecuredByRealEstateBalloonPaymentPeriod	P5Y
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CY2022	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2022
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CY2021Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		usd
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CY2021Q4	us-gaap	Preferred Stock No Par Value PreferredStockNoParValue	0
CY2022Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	1000000
CY2021Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	1000000
CY2022Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0
CY2021Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0
CY2022Q4	us-gaap	Common Stock No Par Value CommonStockNoParValue	0
CY2021Q4	us-gaap	Common Stock No Par Value CommonStockNoParValue	0
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CY2021Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	40000000
CY2022Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	15994884
CY2021Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	15839944
CY2020	us-gaap	Stock Issued During Period Shares Employee Stock Purchase Plans StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans	2264
CY2020	us-gaap	Stock Issued During Period Shares Dividend Reinvestment Plan StockIssuedDuringPeriodSharesDividendReinvestmentPlan	35479
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CY2022Q4	us-gaap	Bank Owned Life Insurance BankOwnedLifeInsurance	80727000	usd
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CY2022	dei	Document Type DocumentType	10-K
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CY2022	dei	Entity File Number EntityFileNumber	000-26719
CY2022	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	MI
CY2022	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	38-3360865
CY2022	dei	Entity Address Address Line1 EntityAddressAddressLine1	310 Leonard Street NW
CY2022	dei	Entity Address City Or Town EntityAddressCityOrTown	Grand Rapids
CY2022	dei	Entity Address State Or Province EntityAddressStateOrProvince	MI
CY2022	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	49504
CY2022	dei	City Area Code CityAreaCode	616
CY2022	dei	Local Phone Number LocalPhoneNumber	406-3000
CY2022	dei	Security12b Title Security12bTitle	Common Stock
CY2022	dei	Trading Symbol TradingSymbol	MBWM
CY2022	dei	Security Exchange Name SecurityExchangeName	NASDAQ
CY2022	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	No
CY2022	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
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CY2022	dei	Entity Filer Category EntityFilerCategory	Accelerated Filer
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CY2022	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
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CY2022	dei	Auditor Firm AuditorFirmId	243
CY2022	dei	Auditor Name AuditorName	BDO USA, LLP
CY2022	dei	Auditor Location AuditorLocation	Grand Rapids, Michigan
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CY2022	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	6550000	usd
CY2021	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	-4300000	usd
CY2020	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	14050000	usd
CY2022	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	151694000	usd
CY2021	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	128362000	usd
CY2020	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	108196000	usd
CY2022	us-gaap	Fees And Commissions Mortgage Banking And Servicing FeesAndCommissionsMortgageBankingAndServicing	8664000	usd
CY2021	us-gaap	Fees And Commissions Mortgage Banking And Servicing FeesAndCommissionsMortgageBankingAndServicing	29959000	usd
CY2020	us-gaap	Fees And Commissions Mortgage Banking And Servicing FeesAndCommissionsMortgageBankingAndServicing	29346000	usd
CY2022	mbwm	Interest Rate Swap Program Fees InterestRateSwapProgramFees	3488000	usd
CY2021	mbwm	Interest Rate Swap Program Fees InterestRateSwapProgramFees	6862000	usd
CY2020	mbwm	Interest Rate Swap Program Fees InterestRateSwapProgramFees	932000	usd
CY2020	mbwm	Fees And Commissions Payroll Processing FeesAndCommissionsPayrollProcessing	1745000	usd
CY2022	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	1678000	usd
CY2021	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	1164000	usd
CY2020	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	1214000	usd
CY2022	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	0	usd
CY2021	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	1058000	usd
CY2020	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	0	usd
CY2022	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	1901000	usd
CY2021	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	2768000	usd
CY2020	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	1384000	usd
CY2020	us-gaap	Labor And Related Expense LaborAndRelatedExpense	59799000	usd
CY2022	us-gaap	Noninterest Income NoninterestIncome	32077000	usd
CY2021	us-gaap	Noninterest Income NoninterestIncome	56220000	usd
CY2020	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	3000	usd
CY2020	us-gaap	Noninterest Income NoninterestIncome	45172000	usd
CY2022	us-gaap	Labor And Related Expense LaborAndRelatedExpense	65124000	usd
CY2022	us-gaap	Occupancy Net OccupancyNet	8362000	usd
CY2021	us-gaap	Occupancy Net OccupancyNet	8088000	usd
CY2020	us-gaap	Occupancy Net OccupancyNet	7950000	usd
CY2022	us-gaap	Equipment Expense EquipmentExpense	3614000	usd
CY2021	us-gaap	Labor And Related Expense LaborAndRelatedExpense	66447000	usd
CY2021	us-gaap	Equipment Expense EquipmentExpense	3654000	usd
CY2020	us-gaap	Equipment Expense EquipmentExpense	3350000	usd
CY2022	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	12359000	usd
CY2021	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	11104000	usd
CY2020	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	10440000	usd
CY2022	us-gaap	Advertising Expense AdvertisingExpense	1445000	usd
CY2021	us-gaap	Advertising Expense AdvertisingExpense	1175000	usd
CY2020	us-gaap	Advertising Expense AdvertisingExpense	1292000	usd
CY2022	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	1239000	usd
CY2021	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	1820000	usd
CY2020	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	1138000	usd
CY2022	mbwm	Charitable Foundation Contribution Expense CharitableFoundationContributionExpense	1514000	usd
CY2021	mbwm	Charitable Foundation Contribution Expense CharitableFoundationContributionExpense	4020000	usd
CY2020	mbwm	Charitable Foundation Contribution Expense CharitableFoundationContributionExpense	0	usd
CY2022	us-gaap	Other Noninterest Expense OtherNoninterestExpense	14324000	usd
CY2021	us-gaap	Other Noninterest Expense OtherNoninterestExpense	14558000	usd
CY2020	us-gaap	Other Noninterest Expense OtherNoninterestExpense	14551000	usd
CY2022	us-gaap	Noninterest Expense NoninterestExpense	107981000	usd
CY2021	us-gaap	Noninterest Expense NoninterestExpense	110866000	usd
CY2020	us-gaap	Noninterest Expense NoninterestExpense	98520000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	75790000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	73716000	usd
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	54848000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	14727000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	14695000	usd
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	10710000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	61063000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	59021000	usd
CY2020	us-gaap	Net Income Loss NetIncomeLoss	44138000	usd
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.85
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.69
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.71
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.85
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.69
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.71
CY2022	us-gaap	Net Income Loss NetIncomeLoss	61063000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	59021000	usd
CY2020	us-gaap	Net Income Loss NetIncomeLoss	44138000	usd
CY2022	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-77990000	usd
CY2021	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-11664000	usd
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	2268000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	-77990000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	-11664000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	2268000	usd
CY2022	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-16378000	usd
CY2021	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-2449000	usd
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	477000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	-16378000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	-2449000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	477000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-61612000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-9215000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	1791000	usd
CY2022	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-549000	usd
CY2021	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	49806000	usd
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	45929000	usd
CY2020	us-gaap	Stock Issued During Period Value Issued For Services StockIssuedDuringPeriodValueIssuedForServices	394000	usd
CY2020	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	17930000	usd
CY2020	us-gaap	Net Income Loss NetIncomeLoss	44138000	usd
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	416561000	usd
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	1791000	usd
CY2020	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	49000	usd
CY2020	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	814000	usd
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	441554000	usd
CY2020	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	2325000	usd
CY2020	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	6591000	usd
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	441554000	usd
CY2021	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	48000	usd
CY2021	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	877000	usd
CY2021	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	50000	usd
CY2021	us-gaap	Stock Issued During Period Value Issued For Services StockIssuedDuringPeriodValueIssuedForServices	344000	usd
CY2021	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	3784000	usd
CY2020	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-1514000	usd
CY2022	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	1678000	usd
CY2021	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	21380000	usd
CY2021	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	18524000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	59021000	usd
CY2021	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-9215000	usd
CY2021Q4	us-gaap	Stockholders Equity StockholdersEquity	456559000	usd
CY2021Q4	us-gaap	Stockholders Equity StockholdersEquity	456559000	usd
CY2022	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	45000	usd
CY2022	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	867000	usd
CY2022	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	36000	usd
CY2022	us-gaap	Stock Issued During Period Value Issued For Services StockIssuedDuringPeriodValueIssuedForServices	359000	usd
CY2022	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	3377000	usd
CY2022	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	19602000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	61063000	usd
CY2022	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-61612000	usd
CY2022Q4	us-gaap	Stockholders Equity StockholdersEquity	441408000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	61063000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	59021000	usd
CY2020	us-gaap	Net Income Loss NetIncomeLoss	44138000	usd
CY2022	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	12945000	usd
CY2021	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	13678000	usd
CY2020	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	9425000	usd
CY2022	mbwm	Discount Accretion On Acquired Loans DiscountAccretionOnAcquiredLoans	-0	usd
CY2021	mbwm	Discount Accretion On Acquired Loans DiscountAccretionOnAcquiredLoans	135000	usd
CY2020	mbwm	Discount Accretion On Acquired Loans DiscountAccretionOnAcquiredLoans	449000	usd
CY2022	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	6550000	usd
CY2021	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	-4300000	usd
CY2020	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	14050000	usd
CY2022	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-1353000	usd
CY2021	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	2020000	usd
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-4141000	usd
CY2022	us-gaap	Share Based Compensation ShareBasedCompensation	3377000	usd
CY2021	us-gaap	Share Based Compensation ShareBasedCompensation	3784000	usd
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	2325000	usd
CY2022	us-gaap	Issuance Of Stock And Warrants For Services Or Claims IssuanceOfStockAndWarrantsForServicesOrClaims	359000	usd
CY2021	us-gaap	Issuance Of Stock And Warrants For Services Or Claims IssuanceOfStockAndWarrantsForServicesOrClaims	344000	usd
CY2020	us-gaap	Issuance Of Stock And Warrants For Services Or Claims IssuanceOfStockAndWarrantsForServicesOrClaims	394000	usd
CY2022	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	237779000	usd
CY2021	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	686418000	usd
CY2020	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	677634000	usd
CY2022	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	217030000	usd
CY2021	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	649245000	usd
CY2020	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	665992000	usd
CY2022	us-gaap	Gain Loss On Sale Of Mortgage Loans GainLossOnSaleOfMortgageLoans	8197000	usd
CY2021	us-gaap	Gain Loss On Sale Of Mortgage Loans GainLossOnSaleOfMortgageLoans	30402000	usd
CY2020	us-gaap	Gain Loss On Sale Of Mortgage Loans GainLossOnSaleOfMortgageLoans	29541000	usd
CY2022	mbwm	Net Gain Loss From Sale And Valuation Write Down Of Foreclosed Assets NetGainLossFromSaleAndValuationWriteDownOfForeclosedAssets	69000	usd
CY2021	mbwm	Net Gain Loss From Sale And Valuation Write Down Of Foreclosed Assets NetGainLossFromSaleAndValuationWriteDownOfForeclosedAssets	78000	usd
CY2020	mbwm	Net Gain Loss From Sale And Valuation Write Down Of Foreclosed Assets NetGainLossFromSaleAndValuationWriteDownOfForeclosedAssets	325000	usd
CY2022	mbwm	Net Gain Loss From Sale And Valuation Write Down Of Former Bank Premises NetGainLossFromSaleAndValuationWriteDownOfFormerBankPremises	-275000	usd
CY2021	mbwm	Net Gain Loss From Sale And Valuation Write Down Of Former Bank Premises NetGainLossFromSaleAndValuationWriteDownOfFormerBankPremises	140000	usd
CY2020	mbwm	Net Gain Loss From Sale And Valuation Write Down Of Former Bank Premises NetGainLossFromSaleAndValuationWriteDownOfFormerBankPremises	27000	usd
CY2022	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	36000	usd
CY2021	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-246000	usd
CY2021	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	1164000	usd
CY2022	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	-0	usd
CY2021	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	1058000	usd
CY2020	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	1214000	usd
CY2020	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	-0	usd
CY2022	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	45000	usd
CY2021	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	-224000	usd
CY2020	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	-24000	usd
CY2022	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	6165000	usd
CY2021	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	-1528000	usd
CY2020	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	917000	usd
CY2022	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	437000	usd
CY2021	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	12655000	usd
CY2020	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	9907000	usd
CY2022	us-gaap	Increase Decrease In Accrued Liabilities And Other Operating Liabilities IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities	32524000	usd
CY2021	us-gaap	Increase Decrease In Accrued Liabilities And Other Operating Liabilities IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities	-3513000	usd
CY2020	us-gaap	Increase Decrease In Accrued Liabilities And Other Operating Liabilities IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities	886000	usd
CY2022	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	119862000	usd
CY2021	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	64573000	usd
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	37877000	usd
CY2022	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	107011000	usd
CY2021	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	298708000	usd
CY2020	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	369682000	usd
CY2022	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	17984000	usd
CY2021	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	80432000	usd
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	321164000	usd
CY2022	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	462427000	usd
CY2021	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	267899000	usd
CY2020	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	341461000	usd
CY2022	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	281000	usd
CY2021	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	0	usd
CY2020	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	0	usd
CY2022	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	4500000	usd
CY2021	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	2000000	usd
CY2020	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	700000	usd
CY2022	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	628000	usd
CY2021	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	0	usd
CY2020	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	0	usd
CY2022	us-gaap	Payments For Proceeds From Businesses And Interest In Affiliates PaymentsForProceedsFromBusinessesAndInterestInAffiliates	-0	usd
CY2021	us-gaap	Payments For Proceeds From Businesses And Interest In Affiliates PaymentsForProceedsFromBusinessesAndInterestInAffiliates	2679000	usd
CY2020	us-gaap	Payments For Proceeds From Businesses And Interest In Affiliates PaymentsForProceedsFromBusinessesAndInterestInAffiliates	-0	usd
CY2022	us-gaap	Payments For Proceeds From Productive Assets PaymentsForProceedsFromProductiveAssets	3017000	usd
CY2021	us-gaap	Payments For Proceeds From Productive Assets PaymentsForProceedsFromProductiveAssets	5602000	usd
CY2020	us-gaap	Payments For Proceeds From Productive Assets PaymentsForProceedsFromProductiveAssets	8989000	usd
CY2022	mbwm	Proceeds From Sale Of Former Bank Premises ProceedsFromSaleOfFormerBankPremises	2994000	usd
CY2021	mbwm	Proceeds From Sale Of Former Bank Premises ProceedsFromSaleOfFormerBankPremises	753000	usd
CY2020	mbwm	Proceeds From Sale Of Former Bank Premises ProceedsFromSaleOfFormerBankPremises	162000	usd
CY2022	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	69000	usd
CY2021	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	196000	usd
CY2020	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	700000	usd
CY2022	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-554999000	usd
CY2021	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-495507000	usd
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-398806000	usd
CY2022	us-gaap	Increase Decrease In Time Deposits IncreaseDecreaseInTimeDeposits	-57189000	usd
CY2021	us-gaap	Increase Decrease In Time Deposits IncreaseDecreaseInTimeDeposits	-120512000	usd
CY2020	us-gaap	Increase Decrease In Time Deposits IncreaseDecreaseInTimeDeposits	-99294000	usd
CY2022	us-gaap	Increase Decrease In Other Deposits IncreaseDecreaseInOtherDeposits	-313193000	usd
CY2021	us-gaap	Increase Decrease In Other Deposits IncreaseDecreaseInOtherDeposits	806796000	usd
CY2020	us-gaap	Increase Decrease In Other Deposits IncreaseDecreaseInOtherDeposits	820463000	usd
CY2022	us-gaap	Proceeds From Payments For In Securities Sold Under Agreements To Repurchase ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase	-3123000	usd
CY2021	us-gaap	Proceeds From Payments For In Securities Sold Under Agreements To Repurchase ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase	79098000	usd
CY2020	us-gaap	Proceeds From Payments For In Securities Sold Under Agreements To Repurchase ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase	15690000	usd
CY2022	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	28263000	usd
CY2021	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	0	usd
CY2020	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	60000000	usd
CY2022	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	94000000	usd
CY2021	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	20000000	usd
CY2020	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	20000000	usd
CY2022	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	14645000	usd
CY2021	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	73635000	usd
CY2021	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	50000	usd
CY2020	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	0	usd
CY2022	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	36000	usd
CY2020	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	3000	usd
CY2022	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	45000	usd
CY2021	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	48000	usd
CY2020	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	49000	usd
CY2022	us-gaap	Proceeds From Issuance Of Common Stock Dividend Reinvestment Plan ProceedsFromIssuanceOfCommonStockDividendReinvestmentPlan	867000	usd
CY2021	us-gaap	Proceeds From Issuance Of Common Stock Dividend Reinvestment Plan ProceedsFromIssuanceOfCommonStockDividendReinvestmentPlan	877000	usd
CY2020	us-gaap	Proceeds From Issuance Of Common Stock Dividend Reinvestment Plan ProceedsFromIssuanceOfCommonStockDividendReinvestmentPlan	814000	usd
CY2022	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	-0	usd
CY2021	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	21380000	usd
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	6591000	usd
CY2022	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	19602000	usd
CY2021	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	18524000	usd
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	17930000	usd
CY2022	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-443251000	usd
CY2021	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	780088000	usd
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	753204000	usd
CY2022	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-878388000	usd
CY2021	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	349154000	usd
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	392275000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents And Federal Funds Sold CashCashEquivalentsAndFederalFundsSold	975160000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents And Federal Funds Sold CashCashEquivalentsAndFederalFundsSold	626006000	usd
CY2019Q4	us-gaap	Cash Cash Equivalents And Federal Funds Sold CashCashEquivalentsAndFederalFundsSold	233731000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents And Federal Funds Sold CashCashEquivalentsAndFederalFundsSold	96772000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents And Federal Funds Sold CashCashEquivalentsAndFederalFundsSold	975160000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents And Federal Funds Sold CashCashEquivalentsAndFederalFundsSold	626006000	usd
CY2022	us-gaap	Interest Paid Net InterestPaidNet	21765000	usd
CY2021	us-gaap	Interest Paid Net InterestPaidNet	20352000	usd
CY2020	us-gaap	Interest Paid Net InterestPaidNet	27703000	usd
CY2022	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	11200000	usd
CY2021	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	17550000	usd
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	10950000	usd
CY2022	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	0	usd
CY2021	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	30000	usd
CY2020	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	146000	usd
CY2022	mbwm	Transfer Of Bank Premises To Other Real Estate Owned TransferOfBankPremisesToOtherRealEstateOwned	0	usd
CY2021	mbwm	Transfer Of Bank Premises To Other Real Estate Owned TransferOfBankPremisesToOtherRealEstateOwned	0	usd
CY2020	mbwm	Transfer Of Bank Premises To Other Real Estate Owned TransferOfBankPremisesToOtherRealEstateOwned	613000	usd
CY2022	mbwm	Transfer Of Bank Premises To Assets Held For Sale TransferOfBankPremisesToAssetsHeldForSale	2847000	usd
CY2021	mbwm	Transfer Of Bank Premises To Assets Held For Sale TransferOfBankPremisesToAssetsHeldForSale	0	usd
CY2020	mbwm	Transfer Of Bank Premises To Assets Held For Sale TransferOfBankPremisesToAssetsHeldForSale	0	usd
CY2022Q4	mbwm	Number Of Unconsolidated Business Trusts Formed To Issue Trust Preferred Securities NumberOfUnconsolidatedBusinessTrustsFormedToIssueTrustPreferredSecurities	5	pure
CY2022	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	292000	usd
CY2022	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	1025000	usd
CY2022	us-gaap	Use Of Estimates UseOfEstimates	<p style="font-family:Times New Roman;font-size:10pt;font-variant:normal;margin:0pt;"><span style="text-decoration: underline; ">Use of Estimates</span>: To prepare financial statements in conformity with accounting principles generally accepted in the United States of America, management makes estimates and assumptions based on available information. These estimates and assumptions affect the amounts reported in the financial statements and the disclosures provided, and actual results could differ. The allowance for credit losses and the fair values of financial instruments are particularly subject to change.</p> <p style="font-family:'Times New Roman';font-size:10pt;font-variant:normal;margin:0pt;"> </p>
CY2022Q4	us-gaap	Financing Receivable Unamortized Loan Fee Cost FinancingReceivableUnamortizedLoanFeeCost	-1000000.0	usd
CY2021Q4	us-gaap	Financing Receivable Unamortized Loan Fee Cost FinancingReceivableUnamortizedLoanFeeCost	2500000	usd
CY2022	mbwm	Interest Income On Commercial And Mortgage Loans Discontinued Period InterestIncomeOnCommercialAndMortgageLoansDiscontinuedPeriod	P90D
CY2022	mbwm	Maximum Delinquency Period For Consumer And Credit Card Loans To Be Charged Off MaximumDelinquencyPeriodForConsumerAndCreditCardLoansToBeChargedOff	P120D
CY2022	mbwm	Financing Receivable Allowance For Credit Loss Allowance Reduction FinancingReceivableAllowanceForCreditLossAllowanceReduction	-900000	usd
CY2022Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	42246000	usd
CY2022Q4	us-gaap	Foreclosed Assets ForeclosedAssets	0	usd
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	37967000	usd
CY2021	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-4300000	usd
CY2021	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	1044000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	685646000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	571000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	83281000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	602936000	usd
CY2021Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	597463000	usd
CY2021Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	5238000	usd
CY2021Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	9958000	usd
CY2021Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	592743000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	193930000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	17438000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	379216000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	65843000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	573146000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	83281000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	351062000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	6455000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	110491000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	3503000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	461553000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	9958000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	732	pure
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	573000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	83300000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	333	pure
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	462000000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	10000000.0	usd
CY2022Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	0	usd
CY2021	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	2740000	usd
CY2021Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	35363000	usd
CY2021Q4	mbwm	Loans Allowance For Credit Losses Individually Evaluated For Impairment LoansAllowanceForCreditLossesIndividuallyEvaluatedForImpairment	546000	usd
CY2022Q4	mbwm	Weighted Average Yield Of Securities Portfolio Due In One Year Or Less WeightedAverageYieldOfSecuritiesPortfolioDueInOneYearOrLess	0.0076	pure
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	21278000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	20732000	usd
CY2022Q4	mbwm	Weighted Average Yield Of Securities Portfolio Due From One To Five Years WeightedAverageYieldOfSecuritiesPortfolioDueFromOneToFiveYears	0.0122	pure
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	249262000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	227357000	usd
CY2022Q4	mbwm	Weighted Average Yield Of Securities Portfolio Due From Five To Ten Years WeightedAverageYieldOfSecuritiesPortfolioDueFromFiveToTenYears	0.0188	pure
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	318700000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	271652000	usd
CY2022Q4	mbwm	Weighted Average Yield Of Securities Portfolio Due Afterten Years WeightedAverageYieldOfSecuritiesPortfolioDueAftertenYears	0.0303	pure
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	57904000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	50742000	usd
CY2022Q4	mbwm	Weighted Average Yield Of Securities Portfolio WeightedAverageYieldOfSecuritiesPortfolio	0.0172	pure
CY2022Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	685646000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	602936000	usd
CY2022	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	0	usd
CY2022Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	3916619000	usd
CY2022Q4	mbwm	Loan Portfolio Classes And Segments As Percentage Of Aggregate Loan LoanPortfolioClassesAndSegmentsAsPercentageOfAggregateLoan	1.000	pure
CY2021Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	3453459000	usd
CY2021Q4	mbwm	Loan Portfolio Classes And Segments As Percentage Of Aggregate Loan LoanPortfolioClassesAndSegmentsAsPercentageOfAggregateLoan	1.000	pure
CY2022	mbwm	Loans And Leases Receivable Net Of Deferred Income Increase Decrease Percentage LoansAndLeasesReceivableNetOfDeferredIncomeIncreaseDecreasePercentage	0.134	pure
CY2022Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	3916619000	usd
CY2022Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	0	usd
CY2021Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	3453459000	usd
CY2021Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	155000	usd
CY2022Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment	1313000	usd
CY2022Q4	us-gaap	Impaired Financing Receivable With Related Allowance Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment	6415000	usd
CY2022Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	2283000	usd
CY2022Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	7728000	usd
CY2022Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	2283000	usd
CY2021Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance	16997000	usd
CY2021Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment	15715000	usd
CY2021	us-gaap	Impaired Financing Receivable With No Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment	19857000	usd
CY2021Q4	us-gaap	Impaired Financing Receivable With Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance	3671000	usd
CY2021Q4	us-gaap	Impaired Financing Receivable With Related Allowance Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment	3651000	usd
CY2021Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	546000	usd
CY2021	us-gaap	Impaired Financing Receivable With Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment	3440000	usd
CY2021Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	20668000	usd
CY2021Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	19366000	usd
CY2021Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	546000	usd
CY2021	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	23297000	usd
CY2021	mbwm	Financing Receivable Accruing Trouble Debt Restructurings Interest Income FinancingReceivableAccruingTroubleDebtRestructuringsInterestIncome	1500000	usd
CY2021	mbwm	Interest Lost On Nonaccrual Loans InterestLostOnNonaccrualLoans	100000	usd
CY2022Q4	us-gaap	Financing Receivable Originated In Current Fiscal Year FinancingReceivableOriginatedInCurrentFiscalYear	1343470000	usd
CY2022Q4	us-gaap	Financing Receivable Originated In Fiscal Year Before Latest Fiscal Year FinancingReceivableOriginatedInFiscalYearBeforeLatestFiscalYear	1016338000	usd
CY2022Q4	us-gaap	Financing Receivable Originated Two Years Before Latest Fiscal Year FinancingReceivableOriginatedTwoYearsBeforeLatestFiscalYear	538303000	usd
CY2022Q4	us-gaap	Financing Receivable Originated Three Years Before Latest Fiscal Year FinancingReceivableOriginatedThreeYearsBeforeLatestFiscalYear	149061000	usd
CY2022Q4	us-gaap	Financing Receivable Originated Four Years Before Latest Fiscal Year FinancingReceivableOriginatedFourYearsBeforeLatestFiscalYear	79881000	usd
CY2022Q4	us-gaap	Financing Receivable Originated Five Or More Years Before Latest Fiscal Year FinancingReceivableOriginatedFiveOrMoreYearsBeforeLatestFiscalYear	115181000	usd
CY2022Q4	mbwm	Financing Receivable Term Loan FinancingReceivableTermLoan	3242234000	usd
CY2022Q4	us-gaap	Financing Receivable Revolving FinancingReceivableRevolving	674385000	usd
CY2022Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	3916619000	usd
CY2021Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	35363000	usd
CY2022	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	6550000	usd
CY2021Q4	mbwm	Loans Collectively Evaluated For Impairment LoansCollectivelyEvaluatedForImpairment	3393983000	usd
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	23889000	usd
CY2020	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	14050000	usd
CY2020	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	838000	usd
CY2021Q4	mbwm	Loans Allowance For Credit Losses Collectively Evaluated For Impairment LoansAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	34817000	usd
CY2021Q4	mbwm	Loans And Leases Receivable Net Of Deferred Income Excluding Ppp Loans LoansAndLeasesReceivableNetOfDeferredIncomeExcludingPPPLoans	3413349000	usd
CY2021Q4	mbwm	Loans Individually Evaluated For Impairment LoansIndividuallyEvaluatedForImpairment	19366000	usd
CY2020	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	866000	usd
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	37967000	usd
CY2020Q4	mbwm	Loans Allowance For Credit Losses Individually Evaluated For Impairment LoansAllowanceForCreditLossesIndividuallyEvaluatedForImpairment	551000	usd
CY2020Q4	mbwm	Loans Allowance For Credit Losses Collectively Evaluated For Impairment LoansAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	37416000	usd
CY2020Q4	mbwm	Loans And Leases Receivable Net Of Deferred Income Excluding Ppp Loans LoansAndLeasesReceivableNetOfDeferredIncomeExcludingPPPLoans	2828211000	usd
CY2020Q4	mbwm	Loans Individually Evaluated For Impairment LoansIndividuallyEvaluatedForImpairment	26958000	usd
CY2020Q4	mbwm	Loans Collectively Evaluated For Impairment LoansCollectivelyEvaluatedForImpairment	2801253000	usd
CY2022	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	10	pure
CY2022	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	7351000	usd
CY2022	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	7350000	usd
CY2021	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	18	pure
CY2021	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	4333000	usd
CY2021	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	4329000	usd
CY2022	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	2	pure
CY2022	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	5665000	usd
CY2021	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	0	pure
CY2021	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	0	usd
CY2021Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	94253000	usd
CY2022Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	38862000	usd
CY2021Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	36955000	usd
CY2022Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	51476000	usd
CY2021Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	57298000	usd
CY2022	us-gaap	Depreciation Depreciation	6000000.0	usd
CY2021	us-gaap	Depreciation Depreciation	5800000	usd
CY2020	us-gaap	Depreciation Depreciation	5200000	usd
CY2022Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P2Y6M
CY2022Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0547	pure
CY2022	us-gaap	Operating Lease Expense OperatingLeaseExpense	1300000	usd
CY2021	us-gaap	Operating Lease Expense OperatingLeaseExpense	1200000	usd
CY2020	us-gaap	Operating Lease Expense OperatingLeaseExpense	1400000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	1091000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	883000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	443000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	339000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	288000	usd
CY2022Q4	us-gaap	Continuing Involvement With Transferred Financial Assets Principal Amount Outstanding ContinuingInvolvementWithTransferredFinancialAssetsPrincipalAmountOutstanding	1376143000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	1589000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	4633000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	1118000	usd
CY2021Q4	us-gaap	Continuing Involvement With Transferred Financial Assets Principal Amount Outstanding ContinuingInvolvementWithTransferredFinancialAssetsPrincipalAmountOutstanding	1344055000	usd
CY2022Q4	mbwm	Continuing Involvement With Transferred Financial Assets Custodial Escrow Balance ContinuingInvolvementWithTransferredFinancialAssetsCustodialEscrowBalance	11600000	usd
CY2021Q4	mbwm	Continuing Involvement With Transferred Financial Assets Custodial Escrow Balance ContinuingInvolvementWithTransferredFinancialAssetsCustodialEscrowBalance	12100000	usd
CY2021Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	12248000	usd
CY2020Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	8189000	usd
CY2022	us-gaap	Servicing Asset At Amortized Value Additions ServicingAssetAtAmortizedValueAdditions	2773000	usd
CY2021	us-gaap	Servicing Asset At Amortized Value Additions ServicingAssetAtAmortizedValueAdditions	7711000	usd
CY2022	us-gaap	Servicing Asset At Amortized Value Amortization1 ServicingAssetAtAmortizedValueAmortization1	3184000	usd
CY2021	us-gaap	Servicing Asset At Amortized Value Amortization1 ServicingAssetAtAmortizedValueAmortization1	3652000	usd
CY2022Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	11837000	usd
CY2021Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	12248000	usd
CY2022Q4	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Balance ValuationAllowanceForImpairmentOfRecognizedServicingAssetsBalance	0	usd
CY2022Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	17700000	usd
CY2021Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	15400000	usd
CY2022	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Discount Rate ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueDiscountRate	0.1125	pure
CY2022	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Prepayment Speed ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValuePrepaymentSpeed	0.066	pure
CY2022	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Expected Credit Losses ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueExpectedCreditLosses	0.0028	pure
CY2021	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Discount Rate ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueDiscountRate	0.080	pure
CY2021	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Prepayment Speed ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValuePrepaymentSpeed	0.074	pure
CY2021	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Expected Credit Losses ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueExpectedCreditLosses	0.0025	pure
CY2022	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Weighted Average Life1 ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueWeightedAverageLife1	P8Y10M24D
CY2021	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Weighted Average Life1 ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueWeightedAverageLife1	P8Y6M
CY2022Q4	mbwm	Mortgage Servicing Rights Amortization Expense Next Twelve Months MortgageServicingRightsAmortizationExpenseNextTwelveMonths	2366000	usd
CY2022Q4	mbwm	Mortgage Servicing Rights Amortization Expense Year Two MortgageServicingRightsAmortizationExpenseYearTwo	2066000	usd
CY2022Q4	mbwm	Mortgage Servicing Rights Amortization Expense Year Three MortgageServicingRightsAmortizationExpenseYearThree	1772000	usd
CY2022Q4	mbwm	Mortgage Servicing Rights Amortization Expense Year Four MortgageServicingRightsAmortizationExpenseYearFour	1492000	usd
CY2022Q4	mbwm	Mortgage Servicing Rights Amortization Expense Year Five MortgageServicingRightsAmortizationExpenseYearFive	1236000	usd
CY2022Q4	mbwm	Mortgage Servicing Rights Amortization Expense After Year Five MortgageServicingRightsAmortizationExpenseAfterYearFive	2905000	usd
CY2021Q4	us-gaap	Finite Lived Core Deposits Gross FiniteLivedCoreDepositsGross	17500000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	16900000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	600000	usd
CY2021Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	16100000	usd
CY2021Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	1400000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	450000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	133000	usd
CY2022Q4	us-gaap	Noninterest Bearing Domestic Deposit Demand NoninterestBearingDomesticDepositDemand	1604750000	usd
CY2022Q4	mbwm	Percentage Of Non Interest Bearing Domestic Deposits To Deposits Demand PercentageOfNonInterestBearingDomesticDepositsToDepositsDemand	0.432	pure
CY2021Q4	us-gaap	Noninterest Bearing Domestic Deposit Demand NoninterestBearingDomesticDepositDemand	1677952000	usd
CY2021Q4	mbwm	Percentage Of Non Interest Bearing Domestic Deposits To Deposits Demand PercentageOfNonInterestBearingDomesticDepositsToDepositsDemand	0.411	pure
CY2022	mbwm	Percentage Of Increase Decrease In Non Interest Bearing Demand Deposits PercentageOfIncreaseDecreaseInNonInterestBearingDemandDeposits	-0.044	pure
CY2022Q4	us-gaap	Interest Bearing Domestic Deposit Checking InterestBearingDomesticDepositChecking	575028000	usd
CY2022Q4	us-gaap	Percentage Of Interest Bearing Domestic Deposits To Deposits Checking PercentageOfInterestBearingDomesticDepositsToDepositsChecking	0.155	pure
CY2021Q4	us-gaap	Interest Bearing Domestic Deposit Checking InterestBearingDomesticDepositChecking	538838000	usd
CY2021Q4	us-gaap	Percentage Of Interest Bearing Domestic Deposits To Deposits Checking PercentageOfInterestBearingDomesticDepositsToDepositsChecking	0.132	pure
CY2022	mbwm	Percentage Of Increase Decrease Of Interest Bearing Checking Deposits PercentageOfIncreaseDecreaseOfInterestBearingCheckingDeposits	0.067	pure
CY2022Q4	us-gaap	Interest Bearing Domestic Deposit Money Market InterestBearingDomesticDepositMoneyMarket	776723000	usd
CY2022Q4	us-gaap	Percentage Of Interest Bearing Domestic Deposits To Deposits Money Market PercentageOfInterestBearingDomesticDepositsToDepositsMoneyMarket	0.209	pure
CY2021Q4	us-gaap	Interest Bearing Domestic Deposit Money Market InterestBearingDomesticDepositMoneyMarket	1040176000	usd
CY2021Q4	us-gaap	Percentage Of Interest Bearing Domestic Deposits To Deposits Money Market PercentageOfInterestBearingDomesticDepositsToDepositsMoneyMarket	0.255	pure
CY2022	mbwm	Percentage Of Increase Decrease In Money Market Deposits PercentageOfIncreaseDecreaseInMoneyMarketDeposits	-0.253	pure
CY2022Q4	us-gaap	Interest Bearing Domestic Deposit Savings InterestBearingDomesticDepositSavings	381602000	usd
CY2022Q4	us-gaap	Percentage Of Interest Bearing Domestic Deposits To Deposits Savings PercentageOfInterestBearingDomesticDepositsToDepositsSavings	0.103	pure
CY2021Q4	us-gaap	Interest Bearing Domestic Deposit Savings InterestBearingDomesticDepositSavings	394330000	usd
CY2021Q4	us-gaap	Percentage Of Interest Bearing Domestic Deposits To Deposits Savings PercentageOfInterestBearingDomesticDepositsToDepositsSavings	0.097	pure
CY2022	mbwm	Percentage Of Increase Or Decrease Of Savings Deposits PercentageOfIncreaseOrDecreaseOfSavingsDeposits	-0.032	pure
CY2022Q4	mbwm	Domestic Time Deposits Less Than100000 DomesticTimeDepositsLessThan100000	113099000	usd
CY2022Q4	mbwm	Percentage Of Domestic Time Deposits Under100000 PercentageOfDomesticTimeDepositsUnder100000	0.030	pure
CY2021Q4	mbwm	Domestic Time Deposits Less Than100000 DomesticTimeDepositsLessThan100000	132776000	usd
CY2021Q4	mbwm	Percentage Of Domestic Time Deposits Under100000 PercentageOfDomesticTimeDepositsUnder100000	0.032	pure
CY2022	mbwm	Percentage Of Increase Decrease In Domestic Time Deposits Under100000 PercentageOfIncreaseDecreaseInDomesticTimeDepositsUnder100000	-0.148	pure
CY2022Q4	mbwm	Domestic Time Deposits100000 Or More DomesticTimeDeposits100000OrMore	261609000	usd
CY2022Q4	mbwm	Percentage Of Domestic Time Deposits100000 And Over PercentageOfDomesticTimeDeposits100000AndOver	0.071	pure
CY2022Q4	us-gaap	Time Deposits100000 Or More TimeDeposits100000OrMore	261609000	usd
CY2021Q4	mbwm	Domestic Time Deposits100000 Or More DomesticTimeDeposits100000OrMore	275208000	usd
CY2021Q4	mbwm	Percentage Of Domestic Time Deposits100000 And Over PercentageOfDomesticTimeDeposits100000AndOver	0.067	pure
CY2022	mbwm	Percentage Of Increase Decrease In Domestic Time Deposits100000 And Over PercentageOfIncreaseDecreaseInDomesticTimeDeposits100000AndOver	-0.049	pure
CY2022Q4	mbwm	Aggregate Local Deposit Liabilities AggregateLocalDepositLiabilities	3712811000	usd
CY2022Q4	mbwm	Aggregate Percentage Of Local Deposits AggregatePercentageOfLocalDeposits	1.000	pure
CY2021Q4	mbwm	Aggregate Local Deposit Liabilities AggregateLocalDepositLiabilities	4059280000	usd
CY2021Q4	mbwm	Aggregate Percentage Of Local Deposits AggregatePercentageOfLocalDeposits	0.994	pure
CY2022	mbwm	Aggregate Percentage Increase Decrease In Local Deposits AggregatePercentageIncreaseDecreaseInLocalDeposits	-0.085	pure
CY2022Q4	mbwm	Out Of Area Time Deposits100000 And Over OutOfAreaTimeDeposits100000AndOver	0	usd
CY2022Q4	mbwm	Percentage Of Out Of Area Time Deposits100000 And Over PercentageOfOutOfAreaTimeDeposits100000AndOver	0.000	pure
CY2021Q4	mbwm	Out Of Area Time Deposits100000 And Over OutOfAreaTimeDeposits100000AndOver	23913000	usd
CY2021Q4	mbwm	Percentage Of Out Of Area Time Deposits100000 And Over PercentageOfOutOfAreaTimeDeposits100000AndOver	0.006	pure
CY2022	mbwm	Percentage Of Increase Decrease In Out Of Area Time100000 And Over PercentageOfIncreaseDecreaseInOutOfAreaTime100000AndOver	-1.000	pure
CY2022Q4	us-gaap	Deposits Deposits	3712811000	usd
CY2022Q4	mbwm	Aggregate Percentage Of Deposits AggregatePercentageOfDeposits	1.000	pure
CY2021Q4	us-gaap	Deposits Deposits	4083193000	usd
CY2021Q4	mbwm	Aggregate Percentage Of Deposits AggregatePercentageOfDeposits	1.000	pure
CY2022	mbwm	Aggregate Increase Decrease In Percentage Of Deposits AggregateIncreaseDecreaseInPercentageOfDeposits	-0.091	pure
CY2022Q4	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	188887000	usd
CY2021Q4	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	260501000	usd
CY2022Q4	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	68434000	usd
CY2021Q4	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	78024000	usd
CY2022Q4	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	22053000	usd
CY2021Q4	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	34595000	usd
CY2022Q4	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	30761000	usd
CY2021Q4	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	7863000	usd
CY2022Q4	us-gaap	Time Deposit Maturities Year Five TimeDepositMaturitiesYearFive	64573000	usd
CY2021Q4	us-gaap	Time Deposit Maturities Year Five TimeDepositMaturitiesYearFive	50914000	usd
CY2022Q4	us-gaap	Time Deposits TimeDeposits	374708000	usd
CY2021Q4	us-gaap	Time Deposits TimeDeposits	431897000	usd
CY2022Q4	us-gaap	Contractual Maturities Time Deposits100000 Or More Three Months Or Less ContractualMaturitiesTimeDeposits100000OrMoreThreeMonthsOrLess	40538000	usd
CY2021Q4	us-gaap	Contractual Maturities Time Deposits100000 Or More Three Months Or Less ContractualMaturitiesTimeDeposits100000OrMoreThreeMonthsOrLess	68887000	usd
CY2022Q4	us-gaap	Contractual Maturities Time Deposits100000 Or More Three Months Through Six Months ContractualMaturitiesTimeDeposits100000OrMoreThreeMonthsThroughSixMonths	25141000	usd
CY2021Q4	us-gaap	Contractual Maturities Time Deposits100000 Or More Three Months Through Six Months ContractualMaturitiesTimeDeposits100000OrMoreThreeMonthsThroughSixMonths	53077000	usd
CY2022Q4	us-gaap	Contractual Maturities Time Deposits100000 Or More Six Months Through12 Months ContractualMaturitiesTimeDeposits100000OrMoreSixMonthsThrough12Months	54394000	usd
CY2021Q4	us-gaap	Contractual Maturities Time Deposits100000 Or More Six Months Through12 Months ContractualMaturitiesTimeDeposits100000OrMoreSixMonthsThrough12Months	56612000	usd
CY2022Q4	us-gaap	Contractual Maturities Time Deposits100000 Or More After12 Months ContractualMaturitiesTimeDeposits100000OrMoreAfter12Months	141536000	usd
CY2021Q4	us-gaap	Contractual Maturities Time Deposits100000 Or More After12 Months ContractualMaturitiesTimeDeposits100000OrMoreAfter12Months	120545000	usd
CY2021Q4	us-gaap	Time Deposits100000 Or More TimeDeposits100000OrMore	299121000	usd
CY2022Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	187000000	usd
CY2021Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	207000000	usd
CY2022	us-gaap	Schedule Of Repurchase Agreements ScheduleOfRepurchaseAgreements	<table border="0" cellpadding="0" cellspacing="0" class="finTable" style="margin-right: 5%; margin-left: 18pt; width: 95%; font-size: 10pt; font-family: "Times New Roman"; text-indent: 0px;"> <tbody> <tr style="vertical-align: bottom;"> <td style="font-family: "Times New Roman"; font-size: 10pt;"> </td> <td style="font-family: "Times New Roman"; font-size: 10pt;"> </td> <td colspan="2" style="text-align: center; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt; border-bottom: 1px solid rgb(0, 0, 0);"> <p style="font-family:Times New Roman;font-size:10pt;font-variant:normal;text-align:center;margin:0pt;">2022</p> </td> <td style="font-family: "Times New Roman"; font-size: 10pt; padding-bottom: 1px;"> </td> <td style="font-family: "Times New Roman"; font-size: 10pt;"> </td> <td colspan="2" style="text-align: center; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt; border-bottom: 1px solid rgb(0, 0, 0);"> <p style="font-family:Times New Roman;font-size:10pt;font-variant:normal;text-align:center;margin:0pt;">2021</p> </td> <td style="font-family: "Times New Roman"; font-size: 10pt; padding-bottom: 1px;"> </td> </tr> <tr style="vertical-align: bottom;"> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> </tr> <tr style="vertical-align: bottom; background-color: rgb(204, 238, 255);"> <td style="font-family: "Times New Roman"; font-size: 10pt; width: 68%;"> <p style="font-family: "Times New Roman"; font-size: 10pt; font-variant: normal; margin: 0pt;">Outstanding balance at year-end</p> </td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt;"> </td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;">$</td> <td style="width: 13%; text-align: right; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;">194,340,000</td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;"> </td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt;"> </td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;">$</td> <td style="width: 13%; text-align: right; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;">197,463,000</td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;"> </td> </tr> <tr style="vertical-align: bottom; background-color: rgb(255, 255, 255);"> <td style="font-family: "Times New Roman"; font-size: 10pt;"> <p style="font-family: "Times New Roman"; font-size: 10pt; font-variant: normal; margin: 0pt;">Weighted average interest rate at year-end</p> </td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt;"> </td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt;"> </td> <td style="width: 13%; text-align: right; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;">0.75</td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;"> <p style="font-family:Times New Roman;font-size:10pt;font-variant:normal;margin:0pt;">%</p> </td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt;"> </td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt;"> </td> <td style="width: 13%; text-align: right; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;">0.11</td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;"> <p style="font-family:Times New Roman;font-size:10pt;font-variant:normal;margin:0pt;">%</p> </td> </tr> <tr style="vertical-align: bottom; background-color: rgb(204, 238, 255);"> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> </tr> <tr style="vertical-align: bottom; background-color: rgb(255, 255, 255);"> <td style="font-family: "Times New Roman"; font-size: 10pt;"> <p style="font-family: "Times New Roman"; font-size: 10pt; font-variant: normal; margin: 0pt;">Average daily balance during the year</p> </td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt;"> </td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;">$</td> <td style="width: 13%; text-align: right; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;">200,499,000</td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;"> </td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt;"> </td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;">$</td> <td style="width: 13%; text-align: right; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;">158,855,000</td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;"> </td> </tr> <tr style="vertical-align: bottom; background-color: rgb(204, 238, 255);"> <td style="font-family: "Times New Roman"; font-size: 10pt;"> <p style="font-family: "Times New Roman"; font-size: 10pt; font-variant: normal; margin: 0pt;">Weighted average interest rate during the year</p> </td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt;"> </td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt;"> </td> <td style="width: 13%; text-align: right; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;">0.15</td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;"> <p style="font-family:Times New Roman;font-size:10pt;font-variant:normal;margin:0pt;">%</p> </td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt;"> </td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt;"> </td> <td style="width: 13%; text-align: right; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;">0.11</td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;"> <p style="font-family:Times New Roman;font-size:10pt;font-variant:normal;margin:0pt;">%</p> </td> </tr> <tr style="vertical-align: bottom; background-color: rgb(255, 255, 255);"> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> </tr> <tr style="vertical-align: bottom; background-color: rgb(204, 238, 255);"> <td style="font-family: "Times New Roman"; font-size: 10pt;"> <p style="font-family: "Times New Roman"; font-size: 10pt; font-variant: normal; margin: 0pt;">Maximum daily balance during the year</p> </td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt;"> </td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;">$</td> <td style="width: 13%; text-align: right; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;">235,577,000</td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;"> </td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt;"> </td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;">$</td> <td style="width: 13%; text-align: right; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;">209,093,000</td> <td style="width: 1%; font-family: "Times New Roman"; font-size: 10pt; margin-left: 0pt;"> </td> </tr> </tbody> </table>
CY2022Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	194340000	usd
CY2021Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	197463000	usd
CY2022	us-gaap	Shortterm Debt Average Outstanding Amount ShorttermDebtAverageOutstandingAmount	200499000	usd
CY2021	us-gaap	Shortterm Debt Average Outstanding Amount ShorttermDebtAverageOutstandingAmount	158855000	usd
CY2022	us-gaap	Shortterm Debt Maximum Amount Outstanding During Period ShorttermDebtMaximumAmountOutstandingDuringPeriod	235577000	usd
CY2021	us-gaap	Shortterm Debt Maximum Amount Outstanding During Period ShorttermDebtMaximumAmountOutstandingDuringPeriod	209093000	usd
CY2022Q4	us-gaap	Line Of Credit Facility Maximum Borrowing Capacity LineOfCreditFacilityMaximumBorrowingCapacity	1030000000.00	usd
CY2022Q4	us-gaap	Line Of Credit Facility Remaining Borrowing Capacity LineOfCreditFacilityRemainingBorrowingCapacity	713000000	usd
CY2022	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	16080000	usd
CY2021	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	12675000	usd
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	14945000	usd
CY2022	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-1353000	usd
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	2020000	usd
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-4141000	usd
CY2022	mbwm	Income Tax Expense Benefit Continuing Operations Change In Valuation Allowance IncomeTaxExpenseBenefitContinuingOperationsChangeInValuationAllowance	0	usd
CY2021	mbwm	Income Tax Expense Benefit Continuing Operations Change In Valuation Allowance IncomeTaxExpenseBenefitContinuingOperationsChangeInValuationAllowance	0	usd
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CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	14727000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	14695000	usd
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	10710000	usd
CY2022	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	15915000	usd
CY2021	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	15481000	usd
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	11518000	usd
CY2022	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	695000	usd
CY2021	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	658000	usd
CY2020	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	681000	usd
CY2022	mbwm	Effective Income Tax Reconciliation Bank Owned Life Insurance EffectiveIncomeTaxReconciliationBankOwnedLifeInsurance	334000	usd
CY2021	mbwm	Effective Income Tax Reconciliation Bank Owned Life Insurance EffectiveIncomeTaxReconciliationBankOwnedLifeInsurance	233000	usd
CY2020	mbwm	Effective Income Tax Reconciliation Bank Owned Life Insurance EffectiveIncomeTaxReconciliationBankOwnedLifeInsurance	238000	usd
CY2022	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	0	usd
CY2021	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	0	usd
CY2020	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	-94000	usd
CY2022	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-159000	usd
CY2021	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	105000	usd
CY2020	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	205000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	14727000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	14695000	usd
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	10710000	usd
CY2022	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21	pure
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	8872000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	7426000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	232000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	259000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	1018000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	941000	usd
CY2022Q4	mbwm	Deferred Tax Assets Non Accrual Loan Interest Income DeferredTaxAssetsNonAccrualLoanInterestIncome	136000	usd
CY2021Q4	mbwm	Deferred Tax Assets Non Accrual Loan Interest Income DeferredTaxAssetsNonAccrualLoanInterestIncome	159000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Unrealized Losses On Availablefor Sale Securities Gross DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross	17369000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Unrealized Losses On Availablefor Sale Securities Gross DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross	991000	usd
CY2022Q4	mbwm	Deferred Tax Assets Lease Liability DeferredTaxAssetsLeaseLiability	810000	usd
CY2021Q4	mbwm	Deferred Tax Assets Lease Liability DeferredTaxAssetsLeaseLiability	749000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Deferred Income DeferredTaxAssetsDeferredIncome	0	usd
CY2021Q4	us-gaap	Deferred Tax Assets Deferred Income DeferredTaxAssetsDeferredIncome	520000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	494000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	595000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	28931000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	11640000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	697000	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	1168000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Prepaid Expenses DeferredTaxLiabilitiesPrepaidExpenses	504000	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Prepaid Expenses DeferredTaxLiabilitiesPrepaidExpenses	416000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	120000	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	276000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Mortgage Servicing Rights DeferredTaxLiabilitiesMortgageServicingRights	2486000	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Mortgage Servicing Rights DeferredTaxLiabilitiesMortgageServicingRights	2572000	usd
CY2022Q4	mbwm	Deferred Tax Liabilities Deferred Loan Fees And Costs DeferredTaxLiabilitiesDeferredLoanFeesAndCosts	211000	usd
CY2021Q4	mbwm	Deferred Tax Liabilities Deferred Loan Fees And Costs DeferredTaxLiabilitiesDeferredLoanFeesAndCosts	0	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	810000	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	749000	usd
CY2022Q4	mbwm	Deferred Tax Liabilities Business Combination Adjustments DeferredTaxLiabilitiesBusinessCombinationAdjustments	1877000	usd
CY2021Q4	mbwm	Deferred Tax Liabilities Business Combination Adjustments DeferredTaxLiabilitiesBusinessCombinationAdjustments	2013000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	326000	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	193000	usd
CY2022Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	7031000	usd
CY2021Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	7387000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	21900000	usd
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CY2022Q4	mbwm	Related Party Deposits And Repurchase Agreements RelatedPartyDepositsAndRepurchaseAgreements	21500000	usd
CY2021Q4	mbwm	Related Party Deposits And Repurchase Agreements RelatedPartyDepositsAndRepurchaseAgreements	18400000	usd
CY2022Q4	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Amount Liability FairValueDisclosureOffbalanceSheetRisksAmountLiability	1908294000	usd
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CY2022	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	2200000	usd
CY2021	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	2100000	usd
CY2020	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	1900000	usd
CY2022	mbwm	Interest Expense Deferred Compensation Plan InterestExpenseDeferredCompensationPlan	100000	usd
CY2020	mbwm	Interest Expense Deferred Compensation Plan InterestExpenseDeferredCompensationPlan	100000	usd
CY2022Q4	us-gaap	Mortgages Held For Sale Fair Value Disclosure MortgagesHeldForSaleFairValueDisclosure	3600000	usd
CY2021Q4	us-gaap	Mortgages Held For Sale Fair Value Disclosure MortgagesHeldForSaleFairValueDisclosure	16700000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	61063000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	59021000	usd
CY2020	us-gaap	Net Income Loss NetIncomeLoss	44138000	usd
CY2022	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	15859889
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	15986857
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	16268689
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.85
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.69
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.71
CY2022	us-gaap	Net Income Loss NetIncomeLoss	61063000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	59021000	usd
CY2020	us-gaap	Net Income Loss NetIncomeLoss	44138000	usd
CY2022	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	15859889
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	15986857
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	16268689
CY2022	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	12
CY2021	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	446
CY2020	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	630
CY2022	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	15859901
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	15987303
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	16269319
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.85
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.69
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.71
CY2022Q4	mbwm	Number Of Business Trusts NumberOfBusinessTrusts	5	pure
CY2022Q4	mbwm	Business Combination Debt Assumed Number Of Trusts BusinessCombinationDebtAssumedNumberOfTrusts	4	pure
CY2014Q2	mbwm	Fair Value Discount Of Subordinated Debentures Related To Assumed Business Trusts At Time Af Merger FairValueDiscountOfSubordinatedDebenturesRelatedToAssumedBusinessTrustsAtTimeAfMerger	15000000.0	usd
CY2014Q2	mbwm	Amortization Of Fair Value Discount Related To Subordinated Debentures Of Assumed Business Trusts AmortizationOfFairValueDiscountRelatedToSubordinatedDebenturesOfAssumedBusinessTrusts	700000	usd
CY2014Q2	mbwm	Amortization Period Of Fair Value Discount Related To Subordinated Debentures Of Assumed Business Trusts AmortizationPeriodOfFairValueDiscountRelatedToSubordinatedDebenturesOfAssumedBusinessTrusts	P21Y6M
CY2022Q4	mbwm	Capital Conservation Buffer CapitalConservationBuffer	0.025	pure
CY2022Q4	mbwm	Common Equity Tier1 Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets CommonEquityTier1RiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets	0.070	pure
CY2022Q4	us-gaap	Tier One Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets	0.085	pure
CY2022Q4	us-gaap	Capital Required For Capital Adequacy To Risk Weighted Assets CapitalRequiredForCapitalAdequacyToRiskWeightedAssets	0.105	pure
CY2022Q4	us-gaap	Statutory Accounting Practices Statutory Amount Available For Dividend Payments Without Regulatory Approval StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApproval	140000000	usd
CY2022Q1	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.31
CY2022Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.32
CY2022Q4	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.32
CY2022Q4	us-gaap	Stock Repurchase Program Remaining Authorized Repurchase Amount1 StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1	6800000	usd
CY2021Q2	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	20000000.0	usd
CY2022	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	0
CY2022Q4	mbwm	Preferred Securities Of Subsidiary Trust PreferredSecuritiesOfSubsidiaryTrust	46900000	usd
CY2021Q4	mbwm	Preferred Securities Of Subsidiary Trust PreferredSecuritiesOfSubsidiaryTrust	46200000	usd
CY2022	mbwm	Maximum Restricted Core Element Allowed In Tier One Capital Percent MaximumRestrictedCoreElementAllowedInTierOneCapitalPercent	0.25	pure
CY2009Q4	mbwm	Maximum Level Of Consolidated Aggregate Assets Allowing For Inclusion Of Trust Preferred Securities In Tier One Capital MaximumLevelOfConsolidatedAggregateAssetsAllowingForInclusionOfTrustPreferredSecuritiesInTierOneCapital	15000000000.0	usd
CY2022Q4	mbwm	Trust Preferred Securities Included In Tier One Capital TrustPreferredSecuritiesIncludedInTierOneCapital	46900000	usd
CY2021Q4	mbwm	Trust Preferred Securities Included In Tier One Capital TrustPreferredSecuritiesIncludedInTierOneCapital	46200000	usd

Files In Submission

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$MBWM
Mercantile Bank Corp Stock $mbwm

2023 Q1 Form 10-K Financial Statement

#000143774923005339 Filed on March 03, 2023

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$MBWM Mercantile Bank Corp Stock $mbwm

2023 Q1 Form 10-K Financial Statement

#000143774923005339 Filed on March 03, 2023

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$MBWM
Mercantile Bank Corp Stock $mbwm