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Recorded Investment in financing receivables.

+ References

No definition available.

+ Details

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Namespace Prefix:	thff_
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- Definition

The balance of financing receivables that were acquired with deteriorated credit quality.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (h)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953423-111524

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- Definition

The valuation allowance for financing receivables acquired with deteriorated credit quality.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953423-111524

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953423-111524

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953423-111524

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- Definition

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

+ References

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- Definition

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

+ References

+ Details

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- 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://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(d))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph d

-Article 9

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (b)(1)(ii)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section L

-Subsection 1

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Allowance for Loan Losses (Details 1) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012
Ending Balance Attributable to Loans
Individually evaluated for impairment	$ 2,590		$ 3,158
Collectively evaluated for impairment	14,793		15,862
Acquired with deteriorated credit quality	872		1,048
Ending Balance	18,255	20,408	20,068	22,133	25,272	21,958
Loans
Individually evaluated for impairment	15,583		18,862
Collectively evaluated for impairment	1,775,091		1,771,562
Acquired with deteriorated credit quality	9,537		10,398
Total	1,800,211		1,800,822
Commercial
Ending Balance Attributable to Loans
Individually evaluated for impairment	2,590		3,158
Collectively evaluated for impairment	7,467		8,421
Acquired with deteriorated credit quality	793		871
Ending Balance	10,850	12,453	12,450	14,531	14,144	10,987
Loans
Individually evaluated for impairment	15,548		18,825
Collectively evaluated for impairment	1,028,728		1,020,771
Acquired with deteriorated credit quality	7,665		8,001
Total	1,051,941		1,047,597
Residential
Ending Balance Attributable to Loans
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	1,295		1,408
Acquired with deteriorated credit quality	79		177
Ending Balance	1,374	1,581	1,585	1,592	5,400	5,426
Loans
Individually evaluated for impairment	35		37
Collectively evaluated for impairment	476,753		481,439
Acquired with deteriorated credit quality	1,872		2,397
Total	478,660		483,873
Consumer
Ending Balance Attributable to Loans
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	3,769		3,650
Acquired with deteriorated credit quality	0		0
Ending Balance	3,769	3,864	3,650	3,637	3,481	3,879
Loans
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	269,610		269,352
Acquired with deteriorated credit quality	0		0
Total	269,610		269,352
Unallocated
Ending Balance Attributable to Loans
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	2,262		2,383
Acquired with deteriorated credit quality	0		0
Ending Balance	$ 2,262	$ 2,510	$ 2,383	$ 2,373	$ 2,247	$ 1,666