GUARANTOR AND NON-GUARANTOR FINANCIAL STATEMENTS (Income Statements) (Details) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenue
Management and leasing fees									$ 18,100,000	$ 15,800,000	$ 12,600,000
Management and leasing fees—related party									36,000,000	24,500,000	14,500,000
Commissions									4,000,000	5,000,000	5,800,000
Commissions—related party									10,000,000	8,000,000	24,200,000
Sale of real estate									10,100,000	2,300,000	400,000
Rental and other income									43,000,000	8,500,000	5,100,000
Total revenue	29,600,000	33,200,000	36,000,000	22,400,000	23,000,000	15,200,000	14,100,000	11,800,000	121,200,000	64,100,000	62,600,000
Operating expenses
Commission and marketing expenses									3,600,000	4,600,000	4,000,000
Compensation and related expenses									76,700,000	55,800,000	41,100,000
Cost of real estate sold									7,900,000	2,200,000	400,000
General and administrative									24,600,000	19,500,000	14,500,000
Rental operating expense									18,900,000	4,500,000	3,300,000
Depreciation and amortization									17,400,000	4,900,000	2,800,000
Total operating expenses	44,000,000	37,300,000	40,100,000	27,600,000	36,900,000	20,800,000	18,400,000	15,400,000	149,100,000	91,500,000	66,100,000
Equity in joint venture income									29,800,000	21,500,000	12,500,000
Interest income from loan pool participations and notes receivable	3,300,000	4,000,000	3,300,000	2,900,000	2,100,000	3,700,000	2,900,000	500,000	13,500,000	9,200,000	8,000,000
Income (loss) from consolidated subsidiaries
Operating income	(2,300,000)	9,300,000	11,100,000	(2,600,000)	(2,700,000)	(100,000)	3,700,000	2,400,000	15,400,000	3,300,000	17,000,000
Non-operating income (expense)
Interest income									300,000	100,000	400,000
Interest income—related party									300,000	2,800,000	2,000,000
Acquisition related gains									56,600,000	25,500,000	6,300,000
Interest Expense									(39,900,000)	(26,100,000)	(19,000,000)
Interest Expense, Other									11,800,000	2,500,000	1,600,000
Gain on sale of marketable securities										4,300,000
Acquisition-related expenses									(1,600,000)	(700,000)
Realized foreign currency exchange loss									(2,800,000)	0	0
Income from continuing operations before benefit from (provision for) income taxes	24,900,000	(2,000,000)	(1,800,000)	(4,500,000)	15,200,000	(6,600,000)	(2,100,000)	200,000	16,500,000	6,700,000	5,100,000
(Provision for) benefit from income taxes	(4,300,000)	(800,000)	500,000	1,700,000	(4,900,000)	2,500,000	1,100,000	1,500,000	(2,900,000)	200,000	2,000,000
Income from continuing operations	20,600,000	(2,800,000)	(1,300,000)	(2,800,000)	10,300,000	(4,100,000)	(1,000,000)	1,700,000	13,600,000	6,900,000	7,100,000
Discontinued Operations
Loss from discontinued operations, net of income taxes		(300,000)							(300,000)
Gain (loss) from sale of real estate, net of income taxes		400,000		200,000				(200,000)	600,000	(200,000)	400,000
Net income	20,600,000	(2,700,000)	(1,300,000)	(2,600,000)	10,300,000	(4,100,000)	(1,000,000)	1,500,000	13,900,000	6,700,000	7,500,000
Net (income) attributable to the noncontrolling interests	(22,900,000)	700,000	900,000	1,000,000	500,000	(100,000)	(100,000)	(2,800,000)	(20,300,000)	(2,500,000)	(1,200,000)
Net (loss) income attributable to Kennedy-Wilson Holdings, Inc.	(2,300,000)	(2,000,000)	(400,000)	(1,600,000)	10,800,000	(4,200,000)	(1,100,000)	(1,300,000)	(6,400,000)	4,200,000	6,300,000
Preferred stock dividends and accretion of issuance costs	(2,000,000)	(2,100,000)	(2,100,000)	(2,000,000)	(2,000,000)	(2,000,000)	(2,100,000)	(2,000,000)	(8,100,000)	(8,100,000)	(8,700,000)
Net loss attributable to Kennedy-Wilson Holdings, Inc. common shareholders	(4,300,000)	(4,100,000)	(2,500,000)	(3,600,000)	8,800,000	(6,200,000)	(3,200,000)	(3,300,000)	(14,500,000)	(3,900,000)	(2,400,000)
Parent [Member]
Revenue
Management and leasing fees
Management and leasing fees—related party
Commissions
Commissions—related party
Sale of real estate
Rental and other income
Total revenue
Operating expenses
Commission and marketing expenses
Compensation and related expenses									7,500,000	8,100,000	5,100,000
Cost of real estate sold
General and administrative									300,000
Rental operating expense
Depreciation and amortization
Total operating expenses									7,800,000	8,100,000	5,100,000
Equity in joint venture income
Interest income from loan pool participations and notes receivable
Income (loss) from consolidated subsidiaries									21,700,000	15,000,000	12,500,000
Operating income									13,900,000	6,900,000	7,400,000
Non-operating income (expense)
Interest income
Interest income—related party
Acquisition related gains
Interest Expense									0	0	0
Interest Expense, Other
Gain on sale of marketable securities										0
Acquisition-related expenses										0
Realized foreign currency exchange loss									0
Income from continuing operations before benefit from (provision for) income taxes									13,900,000	6,900,000	7,400,000
(Provision for) benefit from income taxes
Income from continuing operations									13,900,000	6,900,000	7,400,000
Discontinued Operations
Loss from discontinued operations, net of income taxes
Gain (loss) from sale of real estate, net of income taxes										0	0
Net income									13,900,000	6,900,000	7,400,000
Net (income) attributable to the noncontrolling interests
Net (loss) income attributable to Kennedy-Wilson Holdings, Inc.									13,900,000	6,900,000	7,400,000
Preferred stock dividends and accretion of issuance costs									(8,100,000)	(8,100,000)	(8,700,000)
Net loss attributable to Kennedy-Wilson Holdings, Inc. common shareholders									5,800,000	(1,200,000)	(1,300,000)
Kennedy-Wilson, Inc. [Member]
Revenue
Management and leasing fees										400,000	700,000
Management and leasing fees—related party
Commissions									400,000	500,000	3,300,000
Commissions—related party
Sale of real estate
Rental and other income									100,000
Total revenue									500,000	900,000	4,000,000
Operating expenses
Commission and marketing expenses									300,000	300,000	900,000
Compensation and related expenses									31,900,000	25,700,000	18,100,000
Cost of real estate sold
General and administrative									9,400,000	9,800,000	9,000,000
Rental operating expense
Depreciation and amortization									900,000	300,000	200,000
Total operating expenses									42,500,000	36,100,000	28,200,000
Equity in joint venture income									2,900,000	1,500,000	400,000
Interest income from loan pool participations and notes receivable
Income (loss) from consolidated subsidiaries									105,400,000	66,300,000	51,100,000
Operating income									66,300,000	32,600,000	27,300,000
Non-operating income (expense)
Interest income									100,000	100,000	200,000
Interest income—related party									300,000	2,800,000	2,000,000
Acquisition related gains
Interest Expense									(39,900,000)	(25,600,000)	(19,000,000)
Interest Expense, Other
Gain on sale of marketable securities										4,300,000
Acquisition-related expenses									(200,000)	0
Realized foreign currency exchange loss									0
Income from continuing operations before benefit from (provision for) income taxes									26,600,000	14,200,000	10,500,000
(Provision for) benefit from income taxes									(4,900,000)	700,000	2,000,000
Income from continuing operations									21,700,000	14,900,000	12,500,000
Discontinued Operations
Loss from discontinued operations, net of income taxes
Gain (loss) from sale of real estate, net of income taxes										0	0
Net income									21,700,000	14,900,000	12,500,000
Net (income) attributable to the noncontrolling interests											(100,000)
Net (loss) income attributable to Kennedy-Wilson Holdings, Inc.									21,700,000	14,900,000	12,400,000
Preferred stock dividends and accretion of issuance costs
Net loss attributable to Kennedy-Wilson Holdings, Inc. common shareholders									21,700,000	14,900,000	12,400,000
Guarantor Subsidiaries [Member]
Revenue
Management and leasing fees									5,600,000	9,300,000	3,400,000
Management and leasing fees—related party									16,700,000	10,200,000	13,300,000
Commissions									2,600,000	2,000,000	900,000
Commissions—related party									2,000,000	3,000,000	5,300,000
Sale of real estate									10,100,000	2,300,000	400,000
Rental and other income									6,700,000	1,300,000	1,100,000
Total revenue									43,700,000	28,100,000	24,400,000
Operating expenses
Commission and marketing expenses									2,900,000	3,600,000	2,700,000
Compensation and related expenses									14,800,000	11,600,000	11,800,000
Cost of real estate sold									7,900,000	2,200,000	400,000
General and administrative									5,100,000	3,900,000	3,200,000
Rental operating expense									3,500,000	1,300,000	1,500,000
Depreciation and amortization									4,800,000	900,000	500,000
Total operating expenses									39,000,000	23,500,000	20,100,000
Equity in joint venture income									40,500,000	15,000,000	9,900,000
Interest income from loan pool participations and notes receivable									13,500,000	9,200,000	7,900,000
Income (loss) from consolidated subsidiaries									51,300,000	38,300,000	28,800,000
Operating income									110,000,000	67,100,000	50,900,000
Non-operating income (expense)
Interest income									200,000		200,000
Interest income—related party
Acquisition related gains
Interest Expense									0	(500,000)	0
Interest Expense, Other									1,800,000		300,000
Gain on sale of marketable securities										0
Acquisition-related expenses									(400,000)	(100,000)
Realized foreign currency exchange loss									(2,800,000)
Income from continuing operations before benefit from (provision for) income taxes									105,200,000	66,500,000	50,800,000
(Provision for) benefit from income taxes
Income from continuing operations									105,200,000	66,500,000	50,800,000
Discontinued Operations
Loss from discontinued operations, net of income taxes
Gain (loss) from sale of real estate, net of income taxes									200,000	(200,000)	400,000
Net income									105,400,000	66,300,000	51,200,000
Net (income) attributable to the noncontrolling interests										(300,000)	(400,000)
Net (loss) income attributable to Kennedy-Wilson Holdings, Inc.									105,400,000	66,000,000	50,800,000
Preferred stock dividends and accretion of issuance costs
Net loss attributable to Kennedy-Wilson Holdings, Inc. common shareholders									105,400,000	66,000,000	50,800,000
Non-Guarantor Subsidiaries [Member]
Revenue
Management and leasing fees									12,500,000	6,100,000	8,500,000
Management and leasing fees—related party									19,300,000	14,300,000	1,200,000
Commissions									1,000,000	2,500,000	1,600,000
Commissions—related party									8,000,000	5,000,000	18,900,000
Sale of real estate
Rental and other income									36,200,000	7,200,000	4,000,000
Total revenue									77,000,000	35,100,000	34,200,000
Operating expenses
Commission and marketing expenses									400,000	700,000	400,000
Compensation and related expenses									22,500,000	10,400,000	6,100,000
Cost of real estate sold
General and administrative									9,800,000	5,800,000	2,300,000
Rental operating expense									15,400,000	3,200,000	1,800,000
Depreciation and amortization									11,700,000	3,700,000	2,100,000
Total operating expenses									59,800,000	23,800,000	12,700,000
Equity in joint venture income									(13,600,000)	5,000,000	2,200,000
Interest income from loan pool participations and notes receivable											100,000
Income (loss) from consolidated subsidiaries										100,000
Operating income									3,600,000	16,400,000	23,800,000
Non-operating income (expense)
Interest income
Interest income—related party
Acquisition related gains									56,600,000	25,500,000	6,300,000
Interest Expense									0	0	0
Interest Expense, Other									10,000,000	2,500,000	1,300,000
Gain on sale of marketable securities										0
Acquisition-related expenses									(1,000,000)	(600,000)
Realized foreign currency exchange loss									0
Income from continuing operations before benefit from (provision for) income taxes									49,200,000	38,800,000	28,800,000
(Provision for) benefit from income taxes									2,000,000	(500,000)
Income from continuing operations									51,200,000	38,300,000	28,800,000
Discontinued Operations
Loss from discontinued operations, net of income taxes									(300,000)
Gain (loss) from sale of real estate, net of income taxes									400,000	0	0
Net income									51,300,000	38,300,000	28,800,000
Net (income) attributable to the noncontrolling interests									(20,300,000)	(2,200,000)	(700,000)
Net (loss) income attributable to Kennedy-Wilson Holdings, Inc.									31,000,000	36,100,000	28,100,000
Preferred stock dividends and accretion of issuance costs
Net loss attributable to Kennedy-Wilson Holdings, Inc. common shareholders									31,000,000	36,100,000	28,100,000
Eliminations [Member]
Revenue
Management and leasing fees
Management and leasing fees—related party
Commissions
Commissions—related party
Sale of real estate
Rental and other income
Total revenue
Operating expenses
Commission and marketing expenses
Compensation and related expenses
Cost of real estate sold
General and administrative
Rental operating expense
Depreciation and amortization
Total operating expenses
Equity in joint venture income
Interest income from loan pool participations and notes receivable
Income (loss) from consolidated subsidiaries									(178,400,000)	(119,700,000)	(92,400,000)
Operating income									(178,400,000)	(119,700,000)	(92,400,000)
Non-operating income (expense)
Interest income
Interest income—related party
Acquisition related gains
Interest Expense									0	0	0
Interest Expense, Other
Gain on sale of marketable securities										0
Acquisition-related expenses										0
Realized foreign currency exchange loss									0
Income from continuing operations before benefit from (provision for) income taxes									(178,400,000)	(119,700,000)	(92,400,000)
(Provision for) benefit from income taxes
Income from continuing operations									(178,400,000)	(119,700,000)	(92,400,000)
Discontinued Operations
Loss from discontinued operations, net of income taxes
Gain (loss) from sale of real estate, net of income taxes										0	0
Net income									(178,400,000)	(119,700,000)	(92,400,000)
Net (income) attributable to the noncontrolling interests
Net (loss) income attributable to Kennedy-Wilson Holdings, Inc.									(178,400,000)	(119,700,000)	(92,400,000)
Preferred stock dividends and accretion of issuance costs
Net loss attributable to Kennedy-Wilson Holdings, Inc. common shareholders									$ (178,400,000)	$ (119,700,000)	$ (92,400,000)