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The valuation allowance for financing receivables that are expected to be uncollectible nonimpaired loans that were collectively evaluated for impairment.

No definition available.

Name:	msbi_FinancingReceivableAllowanceForCreditLossesForNonimpairedLoansCollectivelyEvaluatedForImpairment
Namespace Prefix:	msbi_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

The balance of financing receivables nonimpaired loans that were collectively evaluated for impairment.

No definition available.

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Namespace Prefix:	msbi_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

The balance of financing receivables loans acquired with deteriorated credit quality.

No definition available.

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N/A

No definition available.

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- References

No definition available.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Topic 326
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Topic 326
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-Section 50
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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Namespace Prefix:	us-gaap_
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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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Namespace Prefix:	us-gaap_
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The balance of financing receivables that were collectively evaluated for impairment.

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Namespace Prefix:	us-gaap_
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The balance of financing receivables that were individually evaluated for impairment.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Amount, before allowance for credit loss, of financing receivable.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
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