Loans and Leases Receivable

No definition available.

Name:	frme_LoansAndLeasesReceivable
Namespace Prefix:	frme_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

+ Details

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

- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

+ Details

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

- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

+ Details

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

- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707

+ Details

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

- Details

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Loans and Allowance - Allowance for Credit Losses and Loan Portfolio by Loan Segment (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance balances - Individually evaluated for impairment	$ 689	$ 1,872
Allowance balances - Collectively evaluated for impairment	79,595	78,680
Total allowance for loan losses	80,284	80,552	$ 75,032	$ 66,037
Loan balances - Individually evaluated for impairment	11,709	22,025
Loan balances - Collectively evaluated for impairment	8,434,292	7,186,658
Loans	8,459,310	7,224,467
Loans acquired with deteriorated credit quality
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans	13,309	15,784
Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance balances - Individually evaluated for impairment	0	0
Allowance balances - Collectively evaluated for impairment	32,902	32,657
Total allowance for loan losses	32,902	32,657	30,420	27,698
Loan balances - Individually evaluated for impairment	457	1,838
Loan balances - Collectively evaluated for impairment	2,748,681	2,248,330
Loans	2,750,854	2,252,270
Commercial \| Loans acquired with deteriorated credit quality
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans	1,716	2,102
Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance balances - Individually evaluated for impairment	231	1,435
Allowance balances - Collectively evaluated for impairment	28,547	28,174
Total allowance for loan losses	28,778	29,609	27,343	23,661
Loan balances - Individually evaluated for impairment	8,728	17,756
Loan balances - Collectively evaluated for impairment	3,821,660	3,347,686
Loans	3,840,266	3,377,831
Commercial Real Estate \| Loans acquired with deteriorated credit quality
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans	9,878	12,389
Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance balances - Individually evaluated for impairment	0	1
Allowance balances - Collectively evaluated for impairment	4,035	3,963
Total allowance for loan losses	4,035	3,964	3,732	2,923
Loan balances - Individually evaluated for impairment	4	18
Loan balances - Collectively evaluated for impairment	135,985	99,770
Loans	135,989	99,788
Consumer \| Loans acquired with deteriorated credit quality
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans	0	0
Residential
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance balances - Individually evaluated for impairment	458	436
Allowance balances - Collectively evaluated for impairment	14,111	13,886
Total allowance for loan losses	14,569	14,322	$ 13,537	$ 11,755
Loan balances - Individually evaluated for impairment	2,520	2,413
Loan balances - Collectively evaluated for impairment	1,727,966	1,490,872
Loans	1,732,201	1,494,578
Residential \| Loans acquired with deteriorated credit quality
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans	$ 1,715	$ 1,293