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
Mar. 31, 2014	Mar. 31, 2013
Business Acquisition [Line Items]
Pro forma revenues	$ 72.7	$ 34.9
Pro forma net income (loss) attributable to Kennedy-Wilson Holdings, Inc. common shareholders	8.6	(4.3)
Earnings Per Share, Pro Forma [Abstract]
Basic (in dollars per share)	$ 0.10	$ (0.07)
Diluted (in dollars per share)	$ 0.10	$ (0.07)
2013 Acquisitions [Member]
Business Acquisition [Line Items]
Business Acquisition, Pro Forma Equity in Joint Venture Income	$ (0.7)	$ 0.7

Business Acquisition, Pro Forma Equity in Joint Venture Income

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- Definition

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.

+ References

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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.

+ References

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