Real Estate and In-Place Lease Value (Schedule of Pro Forma Information) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Business Acquisition [Line Items]
Pro forma revenues	$ 113.6	$ 78.3	$ 209.1	$ 140.5
Pro forma net income (loss) attributable to Kennedy-Wilson Holdings, Inc. common shareholders	36.9	0.7	46.9	0.1
Earnings Per Share, Pro Forma [Abstract]
Basic (in dollars per share)	$ 0.41	$ 0.01	$ 0.53	$ 0.00
Diluted (in dollars per share)	$ 0.36	$ 0.01	$ 0.46	$ 0.00
2013 Acquisitions [Member]
Business Acquisition [Line Items]
Pro forma income from unconsolidated investments	$ 27.1	$ (0.7)	$ 26.0	$ 2.7

Business Acquisition, Pro Forma Equity in Joint Venture Income

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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.

+ References

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=25497992&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.

+ References

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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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