XML 50 R97.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Note 11 - Federal Income Taxes (Details) (USD $) | Dec. 31, 2014 | Dec. 31, 2013 | Jun. 01, 2014
--- | --- | --- | ---
Note 11 - Federal Income Taxes (Details) [Line Items] |  |  |
Deferred Tax Assets, Valuation Allowance | $ 450,000 us-gaap_DeferredTaxAssetsValuationAllowance | $ 0 us-gaap_DeferredTaxAssetsValuationAllowance |
Federal Alternative Minimum Tax Credits | 2,800,000 mbwm_FederalAlternativeMinimumTaxCredits |  |
Losses on Capital Investments Acquired [Member] |  |  |
Note 11 - Federal Income Taxes (Details) [Line Items] |  |  |
Deferred Tax Assets, Valuation Allowance |  |  | 500,000 us-gaap_DeferredTaxAssetsValuationAllowance / us-gaap_ValuationAllowanceByDeferredTaxAssetAxis = mbwm_LossesOnCapitalInvestmentsAcquiredMember
General Business Tax Credit Carryforward [Member] |  |  |
Note 11 - Federal Income Taxes (Details) [Line Items] |  |  |
Tax Credit Carryforward, Amount | $ 600,000 us-gaap_TaxCreditCarryforwardAmount / us-gaap_TaxCreditCarryforwardAxis = us-gaap_GeneralBusinessMember |  |

X
- Definition Represents the amount of federal alternative minimum tax credits available. + References No definition available. + Details
Name: | mbwm_FederalAlternativeMinimumTaxCredits
Namespace Prefix: | mbwm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | mbwm_Note11FederalIncomeTaxesDetailsLineItems
Namespace Prefix: | mbwm_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319 + Details
Name: | us-gaap_DeferredTaxAssetsValuationAllowance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Carryforwards -URI http://asc.fasb.org/extlink&oid=6506874 + Details
Name: | us-gaap_TaxCreditCarryforwardAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_TaxCreditCarryforwardAxis=us-gaap_GeneralBusinessMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ValuationAllowanceByDeferredTaxAssetAxis=mbwm_LossesOnCapitalInvestmentsAcquiredMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |