Represents the contractual balance of debt securities categorized neither as held-to-maturity nor trading.

No definition available.

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- Definition

Represents the number of collateralized debt obligations which were other than temporarily impaired.

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No definition available.

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- Definition

Represents the contractual balance of debt securities categorized neither as held-to-maturity nor trading, reduced by interest payments received, OTTI charges recorded through earnings to date, OTTI charges recorded in other comprehensive income.

+ References

No definition available.

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- Definition

Available For Sale Securities Present Value Of Future Cash Flows Discount Rate, Basis Point Spread on Variable Rate Basis, Maximum

+ References

No definition available.

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- Definition

Available For Sale Securities Present Value Of Future Cash Flows Discount Rate, Basis Point Spread on Variable Rate Basis, Minimum

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No definition available.

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- Definition

Represents the reference rate for the variable rate of discount rate used to calculate present value of expected future cash flows on available-for-sale securities, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

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- Definition

Rate of credit quality indicator pricing.

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No definition available.

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- Definition

Net of tax amount of cumulative other than temporary impairment (OTTI) on a debt security, categorized as available-for-sale, recognized in other comprehensive income (loss), attributable to the parent entity.

+ References

No definition available.

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- Definition

Cumulative interest received on loans and other debt instruments.

+ References

No definition available.

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- Definition

Represents the gain realized from the sale, exchange, redemption, or retirement of securities, not separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

+ References

No definition available.

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- Definition

Represents the loss realized from the sale, exchange, redemption, or retirement of securities, not separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

+ References

No definition available.

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- Definition

Represents the percentage of severity of other than temporarily impairment (OTTI) on investment securities.

+ References

No definition available.

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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

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-Name Accounting Standards Codification

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position.

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-Name Accounting Standards Codification

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Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

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An amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date more than one year from the balance sheet date, net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

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The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

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The cash inflow associated with principal collections from a borrowing supported by a written promise to pay an obligation.

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

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The fair value of trading securities that serve as collateral for borrowings.

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-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

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SECURITIES: (Details Textual) (USD $)	12 Months Ended		3 Months Ended
SECURITIES: (Details Textual) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 2012	Dec. 31, 2011
Schedule of Available-for-sale Securities [Line Items]
Securities pledged as collateral	$ 412,500,000	$ 361,900,000
Gain on sale of investments	2,000thff_GainOnSaleOfSecuritiesNet	5,000thff_GainOnSaleOfSecuritiesNet
Loss on sale of investments	4,000thff_LossOnSaleOfSecuritiesNet	2,000thff_LossOnSaleOfSecuritiesNet
Number of investment securities with an amortized cost greater than fair value (investments)	108
Cumulative OTTI charges	14,050,000	14,079,000		14,983,000	15,180,000
Amortized Cost	880,946,000	920,897,000
Securities available-for-sale	897,053,000us-gaap_AvailableForSaleSecurities	914,560,000us-gaap_AvailableForSaleSecurities
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	8,189,000	26,684,000
Standard Poors \| Minimum
Schedule of Available-for-sale Securities [Line Items]
Credit quality indicator pricing	45.44
Standard Poors \| Maximum
Schedule of Available-for-sale Securities [Line Items]
Credit quality indicator pricing	92.06
Moody Investor Service \| Minimum
Schedule of Available-for-sale Securities [Line Items]
Credit quality indicator pricing	7.22
Moody Investor Service \| Maximum
Schedule of Available-for-sale Securities [Line Items]
Credit quality indicator pricing	96.04
Other Than Temporarily Impaired Cdo [Member]
Schedule of Available-for-sale Securities [Line Items]
Number of CDO's	3
Contractual balance	25,800,000
Reduced balance	15,100,000
Interest payment received	1,800,000
Cumulative OTTI charges	14,000,000
Other comprehensive income net	5,100,000
Base discount rate, which is subject to an additional margin	3 month LIBOR
Amortized Cost	218,000
Securities available-for-sale	200,000
Other Than Temporarily Impaired Cdo [Member] \| Minimum
Schedule of Available-for-sale Securities [Line Items]
Severity of OTTI (as a percent)	28.00%
Other Than Temporarily Impaired Cdo [Member] \| Maximum
Schedule of Available-for-sale Securities [Line Items]
Severity of OTTI (as a percent)	93.00%
Collateralized debt obligations
Schedule of Available-for-sale Securities [Line Items]
Payment received			1,300,000
CDO payment receivable			$ 200,000
London Interbank Offered Rate (LIBOR) [Member] \| Other Than Temporarily Impaired Cdo [Member]
Schedule of Available-for-sale Securities [Line Items]
Available For Sale Securities Present Value Of Future Cash Flows Discount Rate, Basis Point Spread on Variable Rate Basis, Minimum	1.60%
Available For Sale Securities Present Value Of Future Cash Flows Discount Rate, Basis Point Spread on Variable Rate Basis, Maximum	1.80%