Represents fair value of amended warrant that was reclassified into shareholders' equity during the period.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Termination fees associated with pay-fixed interest rate swaps.

+ References

No definition available.

+ Details

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Namespace Prefix:	ibcp_
Data Type:	xbrli:monetaryItemType
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- Definition

Total monetary amount specified by the derivative asset(s). Expressed as an absolute value.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959

+ Details

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- Definition

Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
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- Definition

Fair value of derivative asset, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 205G

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44C

-Subparagraph a

-Clause 1

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (a),(c)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959

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Balance Type:	debit
Period Type:	instant

- Definition

Fair value of derivative liability, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

+ References

+ Details

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

- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13433-108611

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 45

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 15

-URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13495-108611

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 45

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958

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Namespace Prefix:	us-gaap_
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Balance Type:	debit
Period Type:	instant

- Details

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- Details

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Derivative Financial Instruments (Details) (USD $)	3 Months Ended
Derivative Financial Instruments (Details) (USD $)	Jun. 30, 2013	Apr. 16, 2013	Dec. 31, 2012
Derivative financial instrument according to type of hedge[ Abstract]
Notional Amount	$ 109,561,000
Average Maturity	1 month 6 days
Fair Value	2,375,000
Termination fee	600,000
Fair value of amended warrant was reclassified into shareholders' equity		1,500,000
Fair value of derivative instruments, balance sheet location [Abstract]
Asset Derivatives	2,375,000		1,368,000
Liability Derivatives	0		1,320,000
Cash Flow Hedge [Member]
Fair value of derivative instruments, balance sheet location [Abstract]
Liability Derivatives	0		739,000
No Hedge Designation [Member]
Fair value of derivative instruments, balance sheet location [Abstract]
Asset Derivatives	2,375,000		1,368,000
Liability Derivatives	0		581,000
No Hedge Designation [Member] \| Mandatory Commitments to Sell Mortgage Loans [Member]
Derivative financial instrument according to type of hedge[ Abstract]
Notional Amount	73,369,000
Average Maturity	1 month 6 days
Fair Value	1,999,000
Fair value of derivative instruments, balance sheet location [Abstract]
Asset Derivatives	1,999,000		0
No Hedge Designation [Member] \| Rate-Lock Mortgage Loan Commitments [Member]
Derivative financial instrument according to type of hedge[ Abstract]
Notional Amount	36,192,000
Average Maturity	1 month 6 days
Fair Value	376,000
No Hedge Designation [Member] \| Amended Warrant [Member]
Fair value of derivative instruments, balance sheet location [Abstract]
Asset Derivatives	0		0
Other Assets [Member] \| No Hedge Designation [Member] \| Rate-Lock Mortgage Loan Commitments [Member]
Fair value of derivative instruments, balance sheet location [Abstract]
Asset Derivatives	376,000		1,368,000
Other Liabilities [Member] \| Cash Flow Hedge [Member] \| Pay Fixed Interest-Rate Swap Agreement [Member]
Fair value of derivative instruments, balance sheet location [Abstract]
Liability Derivatives	0		739,000
Other Liabilities [Member] \| No Hedge Designation [Member] \| Mandatory Commitments to Sell Mortgage Loans [Member]
Fair value of derivative instruments, balance sheet location [Abstract]
Liability Derivatives	0		122,000
Other Liabilities [Member] \| No Hedge Designation [Member] \| Amended Warrant [Member]
Fair value of derivative instruments, balance sheet location [Abstract]
Liability Derivatives	$ 0		$ 459,000