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Note 6 - Deposits (Details) - Summary of Deposits (USD $) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2015 | Dec. 31, 2014
Summary of Deposits [Abstract] |  |
Noninterest-bearing checking (in Dollars) | $ 568,843,000 us-gaap_NoninterestBearingDomesticDepositDemand | $ 558,738,000 us-gaap_NoninterestBearingDomesticDepositDemand
Noninterest-bearing checking | 25.00%mbwm_PercentageOfNonInterestBearingDomesticDepositsToDepositsDemand | 24.50%mbwm_PercentageOfNonInterestBearingDomesticDepositsToDepositsDemand
Noninterest-bearing checking | 1.80%mbwm_PercentageOfIncreaseDecreaseInNonInterestBearingDemandDeposits |
Interest-bearing checking (in Dollars) | 417,098,000 us-gaap_InterestBearingDomesticDepositChecking | 413,382,000 us-gaap_InterestBearingDomesticDepositChecking
Interest-bearing checking | 18.30%us-gaap_PercentageOfInterestBearingDomesticDepositsToDepositsChecking | 18.20%us-gaap_PercentageOfInterestBearingDomesticDepositsToDepositsChecking
Interest-bearing checking | 0.90%mbwm_PercentageOfIncreaseDecreaseOfInterestBearingCheckingDeposits |
Money market (in Dollars) | 250,421,000 us-gaap_InterestBearingDomesticDepositMoneyMarket | 235,587,000 us-gaap_InterestBearingDomesticDepositMoneyMarket
Money market | 11.00%us-gaap_PercentageOfInterestBearingDomesticDepositsToDepositsMoneyMarket | 10.30%us-gaap_PercentageOfInterestBearingDomesticDepositsToDepositsMoneyMarket
Money market | 6.30%mbwm_PercentageOfIncreaseDecreaseInMoneyMarketDeposits |
Savings (in Dollars) | 345,459,000 us-gaap_InterestBearingDomesticDepositSavings | 330,459,000 us-gaap_InterestBearingDomesticDepositSavings
Savings | 15.20%us-gaap_PercentageOfInterestBearingDomesticDepositsToDepositsSavings | 14.50%us-gaap_PercentageOfInterestBearingDomesticDepositsToDepositsSavings
Savings | 4.50%mbwm_PercentageOfIncreaseOrDecreaseOfSavingsDeposits |
Time, under $100,000 (in Dollars) | 175,433,000 us-gaap_TimeDepositsLessThan100000 | 181,026,000 us-gaap_TimeDepositsLessThan100000
Time, under $100,000 | 7.70%mbwm_PercentageOfDomesticTimeDepositsUnder100000 | 8.00%mbwm_PercentageOfDomesticTimeDepositsUnder100000
Time, under $100,000 | (3.10%)mbwm_PercentageOfIncreaseDecreaseInDomesticTimeDepositsUnder100000 |
Time, $100,000 and over (in Dollars) | 368,887,000 us-gaap_TimeDeposits100000OrMoreDomestic | 382,120,000 us-gaap_TimeDeposits100000OrMoreDomestic
Time, $100,000 and over | 16.10%mbwm_PercentageOfDomesticTimeDeposits100000AndOver | 16.80%mbwm_PercentageOfDomesticTimeDeposits100000AndOver
Time, $100,000 and over | (3.50%)mbwm_PercentageOfIncreaseDecreaseInDomesticTimeDeposits100000AndOver |
(in Dollars) | 2,126,141,000 mbwm_AggregateLocalDepositLiabilities | 2,101,312,000 mbwm_AggregateLocalDepositLiabilities
| 93.30%mbwm_AggregatePercentageOfLocalDeposits | 92.30%mbwm_AggregatePercentageOfLocalDeposits
| 1.20%mbwm_AggregatePercentageIncreaseDecreaseInLocalDeposits |
Out-of-area time, under $100,000 (in Dollars) | 1,828,000 mbwm_OutOfAreaTimeDepositsUnder100000 | 2,422,000 mbwm_OutOfAreaTimeDepositsUnder100000
Out-of-area time, under $100,000 | 0.10%mbwm_PercentageOfOutOfAreaTimeDepositUnder100000 | 0.10%mbwm_PercentageOfOutOfAreaTimeDepositUnder100000
Out-of-area time, under $100,000 | (24.50%)mbwm_PercentageOfIncreaseDecreaseInOutOfAreaTimeUnder100000 |
Out-of-area time, $100,000 and over (in Dollars) | 151,555,000 mbwm_OutOfAreaTimeDeposits100000AndOver | 173,181,000 mbwm_OutOfAreaTimeDeposits100000AndOver
Out-of-area time, $100,000 and over | 6.60%mbwm_PercentageOfOutOfAreaTimeDeposits100000AndOver | 7.60%mbwm_PercentageOfOutOfAreaTimeDeposits100000AndOver
Out-of-area time, $100,000 and over | (12.50%)mbwm_PercentageOfIncreaseDecreaseInOutOfAreaTime100000AndOver |
(in Dollars) | 153,383,000 mbwm_AggregateOutOfAreaTimeDeposits | 175,603,000 mbwm_AggregateOutOfAreaTimeDeposits
| 6.70%mbwm_AggregatePercentageOfOutOfAreaDeposits | 7.70%mbwm_AggregatePercentageOfOutOfAreaDeposits
| (12.70%)mbwm_AggregatePercentageIncreaseDecreaseInOutOfAreaDeposits |
Total deposits (in Dollars) | $ 2,279,524,000 us-gaap_Deposits | $ 2,276,915,000 us-gaap_Deposits
Total deposits | 100.00%mbwm_AggregatePercentageOfDeposits | 100.00%mbwm_AggregatePercentageOfDeposits
Total deposits | 0.10%mbwm_AggregateIncreaseDecreaseInPercentageOfDeposits |

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- Definition The percentage of increase or (decrease) during the period in deposit liabilities. + References No definition available. + Details
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- Definition Value of liabilities related to local deposits. + References No definition available. + Details
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- Definition Value of liabilities related to out-of-area time deposits. + References No definition available. + Details
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- Definition The percentage of increase or (decrease) during the period in domestic deposit liabilities. + References No definition available. + Details
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- Definition The percentage of increase or (decrease) during the period in out-of-area deposit liabilities. + References No definition available. + Details
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- Definition Represents a percentage of total deposits. + References No definition available. + Details
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- Definition Represents a percentage of domestic deposit liabilities. + References No definition available. + Details
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- Definition Represents a percentage of out-of-area deposits + References No definition available. + Details
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- 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
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- 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
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- 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
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- 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
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- 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
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- 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
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- Definition Percentage of increase or (decrease) in interest-bearing domestic money market demand account deposit liabilities. + References No definition available. + Details
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- 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
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- 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
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- 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
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- Definition Percentage of increase or (decrease) in interest-bearing domestic checking deposit liabilities. + References No definition available. + Details
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- 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
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- 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
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- 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
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- 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
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- 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 + Details
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- 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 + Details
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- 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 + Details
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- 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 + Details
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- 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 + Details
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- Definition Percentage of interest-bearing domestic checking demand deposit liabilities to total deposit liabilities. + References No definition available. + Details
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- Definition Percentage of interest-bearing domestic money market demand account deposit liabilities to total deposit liabilities. + References No definition available. + Details
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- Definition Percentage of interest-bearing domestic savings deposit liabilities to total deposit liabilities. + References No definition available. + Details
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- 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=50488274&loc=d3e64164-112818 + Details
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- 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
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