XML 109 R90.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Note 8 - Deposits (Details) - Summary of Deposits (USD $) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2014 | Dec. 31, 2013
Summary of Deposits [Abstract] |  |
Noninterest-bearing demand (in Dollars) | $ 558,738,000 us-gaap_NoninterestBearingDomesticDepositDemand | $ 224,580,000 us-gaap_NoninterestBearingDomesticDepositDemand
Noninterest-bearing demand | 24.50%mbwm_PercentageOfNonInterestBearingDomesticDepositsToDepositsDemand | 20.10%mbwm_PercentageOfNonInterestBearingDomesticDepositsToDepositsDemand
Noninterest-bearing demand | 148.80%mbwm_PercentageOfIncreaseDecreaseInNonInterestBearingDemandDeposits |
Interest-bearing checking (in Dollars) | 413,382,000 us-gaap_InterestBearingDomesticDepositChecking | 197,388,000 us-gaap_InterestBearingDomesticDepositChecking
Interest-bearing checking | 18.20%us-gaap_PercentageOfInterestBearingDomesticDepositsToDepositsChecking | 17.60%us-gaap_PercentageOfInterestBearingDomesticDepositsToDepositsChecking
Interest-bearing checking | 109.40%mbwm_PercentageOfIncreaseDecreaseOfInterestBearingCheckingDeposits |
Money market (in Dollars) | 235,587,000 us-gaap_InterestBearingDomesticDepositMoneyMarket | 133,369,000 us-gaap_InterestBearingDomesticDepositMoneyMarket
Money market | 10.30%us-gaap_PercentageOfInterestBearingDomesticDepositsToDepositsMoneyMarket | 11.90%us-gaap_PercentageOfInterestBearingDomesticDepositsToDepositsMoneyMarket
Money market | 76.60%mbwm_PercentageOfIncreaseDecreaseInMoneyMarketDeposits |
Savings (in Dollars) | 330,459,000 us-gaap_InterestBearingDomesticDepositSavings | 52,606,000 us-gaap_InterestBearingDomesticDepositSavings
Savings | 14.50%us-gaap_PercentageOfInterestBearingDomesticDepositsToDepositsSavings | 4.70%us-gaap_PercentageOfInterestBearingDomesticDepositsToDepositsSavings
Savings | 528.20%mbwm_PercentageOfIncreaseOrDecreaseOfSavingsDeposits |
Time, under $100,000 (in Dollars) | 181,026,000 us-gaap_TimeDepositsLessThan100000 | 43,251,000 us-gaap_TimeDepositsLessThan100000
Time, under $100,000 | 8.00%mbwm_PercentageOfDomesticTimeDepositsUnder100000 | 3.90%mbwm_PercentageOfDomesticTimeDepositsUnder100000
Time, under $100,000 | 318.50%mbwm_PercentageOfIncreaseDecreaseInDomesticTimeDepositsUnder100000 |
Time, $100,000 and over (in Dollars) | 382,120,000 us-gaap_TimeDeposits100000OrMoreDomestic | 254,600,000 us-gaap_TimeDeposits100000OrMoreDomestic
Time, $100,000 and over | 16.80%mbwm_PercentageOfDomesticTimeDeposits100000AndOver | 22.80%mbwm_PercentageOfDomesticTimeDeposits100000AndOver
Time, $100,000 and over | 50.10%mbwm_PercentageOfIncreaseDecreaseInDomesticTimeDeposits100000AndOver |
(in Dollars) | 2,101,312,000 mbwm_AggregateLocalDepositLiabilities | 905,794,000 mbwm_AggregateLocalDepositLiabilities
| 92.30%mbwm_AggregatePercentageOfLocalDeposits | 81.00%mbwm_AggregatePercentageOfLocalDeposits
| 132.00%mbwm_AggregatePercentageIncreaseDecreaseInLocalDeposits |
Out-of-area time, under $100,000 (in Dollars) | 2,422,000 mbwm_OutOfAreaTimeDepositsUnder100000 | 4,078,000 mbwm_OutOfAreaTimeDepositsUnder100000
Out-of-area time, under $100,000 | 0.10%mbwm_PercentageOfOutOfAreaTimeDepositUnder100000 | 0.40%mbwm_PercentageOfOutOfAreaTimeDepositUnder100000
Out-of-area time, under $100,000 | (40.60%)mbwm_PercentageOfIncreaseDecreaseInOutOfAreaTimeUnder100000 |
Out-of-area time, $100,000 and over (in Dollars) | 173,181,000 mbwm_OutOfAreaTimeDeposits100000AndOver | 209,039,000 mbwm_OutOfAreaTimeDeposits100000AndOver
Out-of-area time, $100,000 and over | 7.60%mbwm_PercentageOfOutOfAreaTimeDeposits100000AndOver | 18.60%mbwm_PercentageOfOutOfAreaTimeDeposits100000AndOver
Out-of-area time, $100,000 and over | (17.20%)mbwm_PercentageOfIncreaseDecreaseInOutOfAreaTime100000AndOver |
(in Dollars) | 175,603,000 mbwm_AggregateOutOfAreaTimeDeposits | 213,117,000 mbwm_AggregateOutOfAreaTimeDeposits
| 7.70%mbwm_AggregatePercentageOfOutOfAreaDeposits | 19.00%mbwm_AggregatePercentageOfOutOfAreaDeposits
| (17.60%)mbwm_AggregatePercentageIncreaseDecreaseInOutOfAreaDeposits |
Total deposits (in Dollars) | $ 2,276,915,000 us-gaap_Deposits | $ 1,118,911,000 us-gaap_Deposits
Total deposits | 100.00%mbwm_AggregatePercentageOfDeposits | 100.00%mbwm_AggregatePercentageOfDeposits
Total deposits | 103.50%mbwm_AggregateIncreaseDecreaseInPercentageOfDeposits |

X
- Definition Percentage of increase or (decrease) in deposit liabilities. + References No definition available. + Details
Name: | mbwm_AggregateIncreaseDecreaseInPercentageOfDeposits
Namespace Prefix: | mbwm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The total amount of local deposits. + References No definition available. + Details
Name: | mbwm_AggregateLocalDepositLiabilities
Namespace Prefix: | mbwm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The total amount of out-of-area time deposits. + References No definition available. + Details
Name: | mbwm_AggregateOutOfAreaTimeDeposits
Namespace Prefix: | mbwm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Percentage of increase or (decrease) in domestic deposit liabilities. + References No definition available. + Details
Name: | mbwm_AggregatePercentageIncreaseDecreaseInLocalDeposits
Namespace Prefix: | mbwm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of increase or (decrease) in out-of-area deposit liabilities. + References No definition available. + Details
Name: | mbwm_AggregatePercentageIncreaseDecreaseInOutOfAreaDeposits
Namespace Prefix: | mbwm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The percentage of total deposits. + References No definition available. + Details
Name: | mbwm_AggregatePercentageOfDeposits
Namespace Prefix: | mbwm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The total percentage of domestic deposit liabilities. + References No definition available. + Details
Name: | mbwm_AggregatePercentageOfLocalDeposits
Namespace Prefix: | mbwm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The total percentage of out-of-area deposits + References No definition available. + Details
Name: | mbwm_AggregatePercentageOfOutOfAreaDeposits
Namespace Prefix: | mbwm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The aggregate amount of out-of-area time deposits (including certificates of deposits, individual retirement accounts and open accounts) in denominations of $100,000 or more. + References No definition available. + Details
Name: | mbwm_OutOfAreaTimeDeposits100000AndOver
Namespace Prefix: | mbwm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The aggregate amount of out-of-area time deposits (including certificates of deposits, individual retirement accounts and open accounts) that total to less than $100,000. + References No definition available. + Details
Name: | mbwm_OutOfAreaTimeDepositsUnder100000
Namespace Prefix: | mbwm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The percentage of domestic time deposit liabilities (including certificates of deposits, individual retirement accounts and open accounts) in denominations of $100,000 or more. + References No definition available. + Details
Name: | mbwm_PercentageOfDomesticTimeDeposits100000AndOver
Namespace Prefix: | mbwm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The percentage of domestic time deposits (including certificates of deposits, individual retirement accounts and open accounts) that total to less than $100,000. + References No definition available. + Details
Name: | mbwm_PercentageOfDomesticTimeDepositsUnder100000
Namespace Prefix: | mbwm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Percentage of increase or (decrease) in domestic time deposit liabilities (including certificates of deposits, individual retirement accounts and open accounts) in denominations of $100,000 or more + References No definition available. + Details
Name: | mbwm_PercentageOfIncreaseDecreaseInDomesticTimeDeposits100000AndOver
Namespace Prefix: | mbwm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of increase or (decrease) in domestic time deposits (including certificates of deposits, individual retirement accounts and open accounts) that total to less than $100,000. + References No definition available. + Details
Name: | mbwm_PercentageOfIncreaseDecreaseInDomesticTimeDepositsUnder100000
Namespace Prefix: | mbwm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of increase or (decrease) in interest-bearing domestic money market demand account deposit liabilities. + References No definition available. + Details
Name: | mbwm_PercentageOfIncreaseDecreaseInMoneyMarketDeposits
Namespace Prefix: | mbwm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of increase or (decrease) in noninterest-bearing domestic accounts that entitle the depositor to withdraw funds at any time without prior notice, also known as demand deposits. + References No definition available. + Details
Name: | mbwm_PercentageOfIncreaseDecreaseInNonInterestBearingDemandDeposits
Namespace Prefix: | mbwm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of increase or (decrease) in out-of-area time deposit liabilities (including certificates of deposits, individual retirement accounts and open accounts) in denominations of $100,000 or more. + References No definition available. + Details
Name: | mbwm_PercentageOfIncreaseDecreaseInOutOfAreaTime100000AndOver
Namespace Prefix: | mbwm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of increase or (decrease) in out-of-area time deposits (including certificates of deposits, individual retirement accounts and open accounts) that total to less than $100,000. + References No definition available. + Details
Name: | mbwm_PercentageOfIncreaseDecreaseInOutOfAreaTimeUnder100000
Namespace Prefix: | mbwm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of increase or (decrease) in interest-bearing domestic checking deposit liabilities. + References No definition available. + Details
Name: | mbwm_PercentageOfIncreaseDecreaseOfInterestBearingCheckingDeposits
Namespace Prefix: | mbwm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of increase or (decrease) in interest-bearing domestic savings deposit liabilities. Saving deposits bear interest and have no stated maturity. + References No definition available. + Details
Name: | mbwm_PercentageOfIncreaseOrDecreaseOfSavingsDeposits
Namespace Prefix: | mbwm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of money in noninterest-bearing domestic accounts that entitle the depositor to withdraw funds at any time without prior notice, also known as demand deposits. + References No definition available. + Details
Name: | mbwm_PercentageOfNonInterestBearingDomesticDepositsToDepositsDemand
Namespace Prefix: | mbwm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The percentage of out-of-area time deposit liabilities (including certificates of deposits, individual retirement accounts and open accounts) in denominations of $100,000 or more. + References No definition available. + Details
Name: | mbwm_PercentageOfOutOfAreaTimeDeposits100000AndOver
Namespace Prefix: | mbwm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The percentage of out-of-area time deposits (including certificates of deposits, individual retirement accounts and open accounts) that total to less than $100,000. + References No definition available. + Details
Name: | mbwm_PercentageOfOutOfAreaTimeDepositUnder100000
Namespace Prefix: | mbwm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

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

X
- Definition The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.12) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 12 -Article 9 + Details
Name: | us-gaap_Deposits
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of interest-bearing domestic checking deposit liabilities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.12) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 12 -Article 9 + Details
Name: | us-gaap_InterestBearingDomesticDepositChecking
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of interest-bearing domestic money market demand account deposit liabilities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.12) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 12 -Article 9 + Details
Name: | us-gaap_InterestBearingDomesticDepositMoneyMarket
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of interest-bearing domestic savings deposit liabilities. Saving deposits bear interest and have no stated maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.12) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 12 -Article 9 + Details
Name: | us-gaap_InterestBearingDomesticDepositSavings
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of money in noninterest-bearing domestic accounts that entitle the depositor to withdraw funds at any time without prior notice, also known as demand deposits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.12) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 12 -Article 9 + Details
Name: | us-gaap_NoninterestBearingDomesticDepositDemand
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Percentage of interest-bearing domestic checking demand deposit liabilities to total deposit liabilities. + References No definition available. + Details
Name: | us-gaap_PercentageOfInterestBearingDomesticDepositsToDepositsChecking
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Percentage of interest-bearing domestic money market demand account deposit liabilities to total deposit liabilities. + References No definition available. + Details
Name: | us-gaap_PercentageOfInterestBearingDomesticDepositsToDepositsMoneyMarket
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Percentage of interest-bearing domestic savings deposit liabilities to total deposit liabilities. + References No definition available. + Details
Name: | us-gaap_PercentageOfInterestBearingDomesticDepositsToDepositsSavings
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The aggregate amount of domestic time deposits (including certificates of deposits, individual retirement accounts and open accounts) in denominations of $100,000 or more. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 405 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6479006&loc=d3e64164-112818 + Details
Name: | us-gaap_TimeDeposits100000OrMoreDomestic
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The aggregate amount of domestic or foreign time deposits (including certificates of deposits, individual retirement accounts and open accounts) that total to less than $100,000. + References No definition available. + Details
Name: | us-gaap_TimeDepositsLessThan100000
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant