KW UNSECURED DEBT - Schedule of Unsecured Debt (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
KW unsecured debt [Member]
Debt Instrument [Line Items]
Debt, net of discount (premium)	$ 1,146,100,000	$ 1,220,300,000
Unamortized loan fees	(14,400,000)	(18,300,000)
Debt	1,131,700,000	1,202,000,000.0
Unamortized discount	3,900,000	4,700,000
Line of Credit [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt, net of discount (premium)	0	75,000,000.0
Senior Notes [Member]
Debt Instrument [Line Items]
Debt, net of discount (premium)	$ 1,146,100,000	$ 1,145,300,000

Long-Term Debt, Net of (Premium) Discount

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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.

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Amount, after accumulated amortization, of debt discount (premium).

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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

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