XML 118 R110.htm IDEA: XBRL DOCUMENT v2.4.1.9

Note 13 - Related Parties (Details) - Loans Outstanding to Directors and Executive Officers (Directors and Executive Officers [Member], USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Directors and Executive Officers [Member]
Related Party Transaction [Line Items]
Beginning balance	$ 6,884,000us-gaap_LoansAndLeasesReceivableRelatedParties / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mbwm_DirectorsAndExecutiveOfficersMember	$ 1,418,000us-gaap_LoansAndLeasesReceivableRelatedParties / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mbwm_DirectorsAndExecutiveOfficersMember
New loans	781,000us-gaap_LoansAndLeasesReceivableRelatedPartiesAdditions / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mbwm_DirectorsAndExecutiveOfficersMember	6,309,000us-gaap_LoansAndLeasesReceivableRelatedPartiesAdditions / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mbwm_DirectorsAndExecutiveOfficersMember
Repayments	(381,000)us-gaap_LoansAndLeasesReceivableRelatedPartiesCollections / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mbwm_DirectorsAndExecutiveOfficersMember	(252,000)us-gaap_LoansAndLeasesReceivableRelatedPartiesCollections / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mbwm_DirectorsAndExecutiveOfficersMember
Adjustments	1,718,000mbwm_LoansAndLeasesReceivableRelatedPartiesAdjustments / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mbwm_DirectorsAndExecutiveOfficersMember	(591,000)mbwm_LoansAndLeasesReceivableRelatedPartiesAdjustments / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mbwm_DirectorsAndExecutiveOfficersMember
Ending balance	$ 9,002,000us-gaap_LoansAndLeasesReceivableRelatedParties / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mbwm_DirectorsAndExecutiveOfficersMember	$ 6,884,000us-gaap_LoansAndLeasesReceivableRelatedParties / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = mbwm_DirectorsAndExecutiveOfficersMember

X

- Definition

Represents the addition (reduction) in related party's loan balances due to the Firstbank merger and Board member retirements.

+ References

No definition available.

+ Details

Name:	mbwm_LoansAndLeasesReceivableRelatedPartiesAdjustments
Namespace Prefix:	mbwm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(e))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph e

-Article 9

+ Details

Name:	us-gaap_LoansAndLeasesReceivableRelatedParties
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Reflects the amount of new advances made to related parties in the form of loan and lease receivables.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(e))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph e

-Article 9

+ Details

Name:	us-gaap_LoansAndLeasesReceivableRelatedPartiesAdditions
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Reflects the amount of collections received from related parties to reduce the carrying amounts of loans and leases receivable due from them.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(e))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph e

-Article 9

+ Details

Name:	us-gaap_LoansAndLeasesReceivableRelatedPartiesCollections
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Details

Name:	us-gaap_RelatedPartyTransactionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration