Real Estate and In-Place Lease Value - Schedule of Pro Forma Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Real Estate [Abstract]
Pro forma revenues	$ 172.6	$ 138.3
Pro forma net income (loss) attributable to Kennedy-Wilson Holdings, Inc. common shareholders	$ (7.0)	$ (3.0)
Pro forma net loss per share:
Basic (in dollars per share)	$ (0.06)	$ (0.03)
Diluted (in dollars per share)	$ (0.06)	$ (0.03)

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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