Name:	mbwm_CapitalConservationBuffer
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The maximum level of consolidated aggregate assets allowing for inclusion of trust preferred securities in Tier 1 Capital under the Dodd-Frank Act.

No definition available.

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Data Type:	xbrli:monetaryItemType
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The maximum amount of restricted core elements allowed in tier one capital expressed as a percent.

No definition available.

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Trust preferred securities possesses characteristics of both equity and debt issues and are generally issued by bank holding companies.

No definition available.

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Additional amount of stock repurchase plan authorized.

No definition available.

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Aggregate dividends declared during the period for each share of common stock outstanding.

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-Name Accounting Standards Codification
-Topic 505
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-Section S99
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Date the declared dividend will be paid, in CCYY-MM-DD format.

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Amount of stock repurchase plan authorized.

No definition available.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Total cost of shares repurchased divided by the total number of shares repurchased.

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