SEGMENT REPORTING (Details) - USD ($) $ in Thousands	3 Months Ended								4 Months Ended	8 Months Ended	12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Apr. 30, 2014	Dec. 31, 2014	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information
Net income (loss) attributable to noncontrolling interests										$ (6,000)	$ (11,800)	$ (23,400)
Total assets	$ 5,851,057				$ 7,788,395						5,851,057	7,788,395
Predecessor Company
Segment Reporting Information
Total revenues									$ 217,242
Total investment costs and expenses									101,825
Total other income (loss)									56,334
Total other expenses									65,609
Income tax expense (benefit)									162
Net income (loss)									105,980
Net income (loss) attributable to noncontrolling interests									0
Net income (loss) attributable to KKR Financial Holdings LLC and Subsidiaries									105,980
Total CLO management fees									29,841
Predecessor Company | Reportable Segments | Credit
Segment Reporting Information
Total revenues									134,255
Total investment costs and expenses									62,485
Total other income (loss)									76,046
Total other expenses									23,121
Income tax expense (benefit)									146
Net income (loss)									124,549
Net income (loss) attributable to noncontrolling interests									0
Net income (loss) attributable to KKR Financial Holdings LLC and Subsidiaries									124,549
Predecessor Company | Reportable Segments | Natural Resources
Segment Reporting Information
Total revenues									61,782
Total investment costs and expenses									38,915
Total other income (loss)									(8,123)
Total other expenses									1,633
Income tax expense (benefit)									0
Net income (loss)									13,111
Net income (loss) attributable to noncontrolling interests									0
Net income (loss) attributable to KKR Financial Holdings LLC and Subsidiaries									13,111
Predecessor Company | Reportable Segments | Other
Segment Reporting Information
Total revenues									21,205
Total investment costs and expenses									425
Total other income (loss)									(11,589)
Total other expenses									230
Income tax expense (benefit)									16
Net income (loss)									8,945
Net income (loss) attributable to noncontrolling interests									0
Net income (loss) attributable to KKR Financial Holdings LLC and Subsidiaries									8,945
Predecessor Company | Reconciling Items
Segment Reporting Information
Total revenues									0
Total investment costs and expenses									0
Total other income (loss)									0
Total other expenses									40,625
Income tax expense (benefit)									0
Net income (loss)									(40,625)
Net income (loss) attributable to noncontrolling interests									0
Net income (loss) attributable to KKR Financial Holdings LLC and Subsidiaries									(40,625)
Total CLO management fees									12,900
Successor Company
Segment Reporting Information
Total revenues	62,588	$ 71,017	$ 69,162	$ 89,305	82,670	$ 89,109	$ 105,691	$ 97,786		350,345	292,072	375,256
Total investment costs and expenses	48,846	130,593	58,053	52,998	53,202	50,352	62,450	57,653		181,136	290,490	223,657
Total other income (loss)	58,176	213,366	24,946	(209,882)	(186,065)	(185,449)	8,035	(69,164)		(344,382)	86,606	(432,643)
Total other expenses	15,021	17,141	9,192	24,064	11,457	11,547	12,269	17,168		43,572	65,418	52,441
Income tax expense (benefit)	1,176	340	(187)	60	20	94	729	347		484	1,389	1,190
Net income (loss)	55,721	136,309	27,050	(197,699)	(168,074)	(158,333)	38,278	(46,546)		(219,229)	21,381	(334,675)
Net income (loss) attributable to noncontrolling interests	3,545	1,492	(1,281)	(15,535)	(7,977)	(6,676)	(2,705)	(6,071)		(5,956)	(11,779)	(23,429)
Net income (loss) attributable to KKR Financial Holdings LLC and Subsidiaries	52,176	$ 134,817	$ 28,331	$ (182,164)	(160,097)	$ (151,657)	$ 40,983	$ (40,475)		(213,273)	33,160	(311,246)
Total CLO management fees										33,764	30,504	38,086
Successor Company | Reportable Segments | Credit
Segment Reporting Information
Total revenues										279,639	268,042	339,809
Total investment costs and expenses										142,204	282,616	214,464
Total other income (loss)										(241,035)	100,547	(391,187)
Total other expenses										40,703	64,318	50,631
Income tax expense (benefit)										49	121	154
Net income (loss)										(144,352)	21,534	(316,627)
Net income (loss) attributable to noncontrolling interests										(1,797)	(7,295)	(16,071)
Net income (loss) attributable to KKR Financial Holdings LLC and Subsidiaries										(142,555)	28,829	(300,556)
Total assets	5,422,560				7,303,305						5,422,560	7,303,305
Successor Company | Reportable Segments | Natural Resources
Segment Reporting Information
Total revenues										57,616	10,131	15,677
Total investment costs and expenses										38,117	6,224	7,625
Total other income (loss)										(115,141)	(7,126)	(70,630)
Total other expenses										2,219	635	1,179
Income tax expense (benefit)										0	0	0
Net income (loss)										(97,861)	(3,854)	(63,757)
Net income (loss) attributable to noncontrolling interests										(4,159)	(4,484)	(7,358)
Net income (loss) attributable to KKR Financial Holdings LLC and Subsidiaries										(93,702)	630	(56,399)
Total assets	219,516				230,815						219,516	230,815
Successor Company | Reportable Segments | Other
Segment Reporting Information
Total revenues										13,090	13,899	19,770
Total investment costs and expenses										815	1,650	1,568
Total other income (loss)										11,794	(6,815)	29,174
Total other expenses										476	465	412
Income tax expense (benefit)										435	1,268	1,036
Net income (loss)										23,158	3,701	45,928
Net income (loss) attributable to noncontrolling interests										0	0	0
Net income (loss) attributable to KKR Financial Holdings LLC and Subsidiaries										23,158	3,701	45,928
Total assets	208,981				254,275						208,981	254,275
Successor Company | Reconciling Items
Segment Reporting Information
Total revenues										0	0	0
Total investment costs and expenses										0	0	0
Total other income (loss)										0	0	0
Total other expenses										174	0	219
Income tax expense (benefit)										0	0	0
Net income (loss)										(174)	0	(219)
Net income (loss) attributable to noncontrolling interests										0	0	0
Net income (loss) attributable to KKR Financial Holdings LLC and Subsidiaries										(174)	0	(219)
Total assets	0				0						0	0
Noncontrolling interests | Successor Company
Segment Reporting Information
Net income (loss)										$ (5,956)	(11,779)	(23,429)
Total assets	71,600				82,900						71,600	82,900
Noncontrolling interests | Successor Company | Reportable Segments | Credit
Segment Reporting Information
Total assets	43,400				50,300						43,400	50,300
Noncontrolling interests | Successor Company | Reportable Segments | Natural Resources
Segment Reporting Information
Total assets	$ 28,200				$ 32,600						$ 28,200	$ 32,600
Merger Transaction Costs | Predecessor Company | Reconciling Items
Segment Reporting Information
Total CLO management fees									$ 22,700