Debt Instrument, Principal Value

No definition available.

Name:	kfs_DebtInstrumentPrincipalValue
Namespace Prefix:	kfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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-Topic 210
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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

Amount, after accumulated amortization, of debt premium.

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+ Details

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

- Definition

For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

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+ Details

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

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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+ Details

Name:	us-gaap_LongTermDebtCurrent
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

Name:	us-gaap_LongTermDebtFairValue
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Including the current and noncurrent portions, the carrying value as of the balance sheet date of notes payable to banks, excluding mortgage notes, initially due beyond one year or beyond the operating cycle if longer.

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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount, before tax and reclassification adjustment, of unrealized gain (loss) from increase (decrease) in instrument-specific credit risk of financial liability measured under fair value option.

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Balance Type:	credit
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Period Type:

Debt Debt (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
Debt Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Oct. 12, 2017	Jul. 14, 2016	Oct. 15, 2015	Jan. 05, 2015
Debt Instrument [Line Items]
Long-term Debt, Fair Value	$ 189,702		$ 189,702		$ 187,172
Debt Instrument, Face Amount							$ 180,000
Debt Instrument, Unamortized Premium							$ 11,700
Debt Instrument, Interest Rate, Stated Percentage							4.07%	10.25%	4.81%
Debt Instrument, Principal Value	285,475		285,475		288,732
Change in fair value of debt attributable to instrument-specific credit risk	658	$ 0
Loss on change in fair value of debt	(1,450)	$ (1,178)	(2,511)	$ (5,769)
Bank loan	4,167		4,167		4,917
Long-term Debt [Member]
Debt Instrument [Line Items]
Long-term Debt, Fair Value							$ 191,700
Debt Instrument, Principal Value	190,808		190,808		193,315
Notes Payable to Banks [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage						5.00%
Debt Instrument, Principal Value	4,167		4,167		4,917	$ 5,000
Long-term Debt, Current Maturities	$ 3,770		$ 3,770		$ 4,864