CORPORATE LOANS AND ALLOWANCE FOR LOAN LOSSES (Details) (Successor Company, USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Summary of corporate loans
Par	$ 6,304,720kfn_LoansAndLeasesReceivablePar	$ 6,907,373kfn_LoansAndLeasesReceivablePar
Amortized Cost	6,153,832	6,710,570
Estimated Fair Value	6,031,524	6,506,564
Corporate loans, at estimated fair value
Summary of corporate loans
Par	6,304,720	6,907,373
Amortized Cost	6,153,832	6,710,570
Estimated Fair Value	$ 6,031,524	$ 6,506,564

Represents the amount of par of loans and leases held in portfolio, including but not limited to, commercial and consumer loans.

No definition available.

+ Details

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Namespace Prefix:	kfn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes 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 310

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5074-111524

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

+ Details

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

- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Glossary Loan

-URI http://asc.fasb.org/extlink&oid=6517073

+ Details

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Balance Type:	debit
Period Type:	instant