XML 74 R60.htm IDEA: XBRL DOCUMENT
v3.3.1.900

Note 2 - Business Combination (Details) - Pro Forma Information - Firstbank Corporation [Member] | 12 Months Ended
--- | ---
Dec. 31, 2014 USD ($) $ / shares
Note 2 - Business Combination (Details) - Pro Forma Information [Line Items] |
Net interest income | $ 98,607,000
Noninterest expense | 81,295,000
Net income | $ 22,659,000
Net income per diluted share (in Dollars per share) | $ / shares | $ 1.33

X
- Definition The pro forma net interest Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period. + References No definition available. + Details
Name: | mbwm_BusinessAcquisitionsProFormaNetInterestIncome
Namespace Prefix: | mbwm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The pro forma noninterest expense for the period as if the business combination or combinations had been completed at the beginning of a period. + References No definition available. + Details
Name: | mbwm_BusinessAcquisitionsProFormaNoninterestExpense
Namespace Prefix: | mbwm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | mbwm_Note2BusinessCombinationDetailsProFormaInformationLineItems
Namespace Prefix: | mbwm_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(2)-(3) -URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463 + Details
Name: | us-gaap_BusinessAcquisitionProFormaEarningsPerShareDiluted
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(2)-(3) -URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463 + Details
Name: | us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=mbwm_FirstbankCorporationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |