Represents the aggregate distributions to the parent, including cash, assets, and/or equity.

No definition available.

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Balance Type:	debit
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- Definition

Represents the number of issuers of the investments in which the reporting entity invested.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

Represents the fees waived by the related party.

+ References

No definition available.

+ Details

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

- Definition

Represents the minimum affirmative votes required of the entity's independent directors for the termination of the management agreement.

+ References

No definition available.

+ Details

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- Definition

Represents the prior notice period for termination of Management Agreement.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
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- Definition

Represents the renewal term of the management agreement each December 31 unless terminated upon by vote.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
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- Definition

Represents the number of times the sum of the average annual base management fee and the average annual incentive fee for the first two 12-month periods is multiplied to determine the termination fee.

+ References

No definition available.

+ Details

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- Definition

Represents the specified period immediately preceding the date of termination for which the average annual incentive fee is considered for the calculation of the termination fee.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
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- Definition

Represents the number of times the specified period for which the average annual incentive fee needs to be considered for the calculation of termination fee.

+ References

No definition available.

+ Details

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- Definition

Represents the percentage of ownership in subordinated note.

+ References

No definition available.

+ Details

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Namespace Prefix:	kfn_
Data Type:	num:percentItemType
Balance Type:	na
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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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

Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 320
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 1
-Subparagraph (c)
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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

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MANAGEMENT AGREEMENT AND RELATED PARTY TRANSACTIONS (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2016 USD ($) issuer period	Mar. 31, 2015 USD ($)	Dec. 31, 2015 USD ($) issuer
Management Agreement and Related Party Transactions
Related party transaction expense	$ 7,276,000	$ 10,220,000
Distribution to parent	$ 38,314,000	55,163,000
CLO Management Fees \| Maximum
Management Agreement and Related Party Transactions
Entity's percentage in subordinated notes	100.00%
CLO Management Fees \| CLO 2013-1, CLO 2013-2, and CLO 10
Management Agreement and Related Party Transactions
Entity's percentage in subordinated notes	100.00%
Manager
Management Agreement and Related Party Transactions
Renewal period (in years)	1 year
Votes for termination, minimum (as a percent)	66.70%
Notice period for termination (in days)	180 days
Multiplier used to determine termination fee	4
Number of 12 month periods considered for calculation of termination fee (in periods) \| period	2
Specified period for which average annual incentive fee to be considered (in months)	12 months
Manager \| Base Management Fees
Management Agreement and Related Party Transactions
Related party transaction expense	$ 1,029,000	4,053,000
Manager \| Incentive Fees
Management Agreement and Related Party Transactions
Related party transaction expense	0	0
Manager \| Reimbursable General And Administrative Expenses
Management Agreement and Related Party Transactions
Related party transaction expense	1,000,000	2,300,000
Collateral manager \| CLO Management Fees
Management Agreement and Related Party Transactions
Fees, waived		500,000
Related party transaction expense	$ 6,247,000	$ 6,167,000
Affiliated Entity
Management Agreement and Related Party Transactions
Investment in affiliates, number of issuers \| issuer	6		8
Estimated fair value	$ 655,400,000		$ 734,300,000
Percent to total investment in corporate loans, debt securities and other investments \| Affiliated Investments \| Affiliated Entity
Management Agreement and Related Party Transactions
Concentration risk (as a percent)	11.00%		11.00%
Corporate loans, at estimated fair value \| Affiliated Entity
Management Agreement and Related Party Transactions
Estimated fair value	$ 644,400,000
Equity Investments, at Estimated Fair Value \| Affiliated Entity
Management Agreement and Related Party Transactions
Estimated fair value	11,000,000		$ 11,000,000
Corporate loans \| Affiliated Entity
Management Agreement and Related Party Transactions
Estimated fair value			723,300,000
Joint Ventures And Partnerships \| Affiliated Entity
Management Agreement and Related Party Transactions
Estimated fair value	$ 685,300,000		$ 805,500,000