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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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Period Type:	instant

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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

+ Details

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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	Sep. 30, 2013	Jun. 30, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Dec. 31, 2011
Ending Balance Attributable to Loans
Individually evaluated for impairment	$ 5,510		$ 7,373
Collectively evaluated for impairment	15,498		14,337
Acquired with deteriorated credit quality	996		248
Ending Balance	22,004	22,133	21,958	21,457	20,092	19,241
Loans
Individually evaluated for impairment	24,967		30,694
Collectively evaluated for impairment	1,780,028		1,814,229
Acquired with deteriorated credit quality	12,878		17,009
Total	1,817,873		1,861,932
Commercial
Ending Balance Attributable to Loans
Individually evaluated for impairment	5,510		3,453
Collectively evaluated for impairment	7,698		7,286
Acquired with deteriorated credit quality	810		248
Ending Balance	14,018	14,531	10,987	13,407	13,190	12,119
Loans
Individually evaluated for impairment	24,741		23,721
Collectively evaluated for impairment	1,028,446		1,056,861
Acquired with deteriorated credit quality	10,142		13,582
Total	1,063,329		1,094,164
Residential
Ending Balance Attributable to Loans
Individually evaluated for impairment	0		3,920
Collectively evaluated for impairment	1,254		1,506
Acquired with deteriorated credit quality	186		0
Ending Balance	1,440	1,592	5,426	3,373	2,124	2,728
Loans
Individually evaluated for impairment	226		6,973
Collectively evaluated for impairment	481,064		487,486
Acquired with deteriorated credit quality	2,736		3,421
Total	484,026		497,880
Consumer
Ending Balance Attributable to Loans
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	3,625		3,879
Acquired with deteriorated credit quality	0		0
Ending Balance	3,625	3,637	3,879	3,558	3,744	3,889
Loans
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	270,518		269,882
Acquired with deteriorated credit quality	0		6
Total	270,518		269,888
Unallocated
Ending Balance Attributable to Loans
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	2,921		1,666
Acquired with deteriorated credit quality	0		0
Ending Balance	$ 2,921	$ 2,373	$ 1,666	$ 1,119	$ 1,034	$ 505