Stockholders' Equity Stockholders' Equity (Noncontrolling Interests) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2014 JointVenture	Dec. 31, 2013
Noncontrolling Interest [Line Items]
Noncontrolling Interest, Increase from Subsidiary Equity Issuance	$ 2.9
Number of Joint Venture Investments Consolidated	6
Consolidation of noncontrolling interests (Note 4)	167.9
Noncontrolling interests	1,671.6	50.6
KWE [Member]
Noncontrolling Interest [Line Items]
Ownership percentage by parent	12.20%
Noncontrolling Interest, Increase from Subsidiary Equity Issuance	1,409.1
Noncontrolling Interest [Member]
Noncontrolling Interest [Line Items]
Noncontrolling Interest, Increase from Subsidiary Equity Issuance	2.9
Consolidation of noncontrolling interests (Note 4)	167.9
Noncontrolling interests	1,671.6	50.6
Noncontrolling Interest [Member] \| KWE [Member]
Noncontrolling Interest [Line Items]
Noncontrolling Interest, Increase from Subsidiary Equity Issuance	1,415.6
Additional Paid-in Capital [Member] \| KWE [Member]
Noncontrolling Interest [Line Items]
Noncontrolling Interest, Increase from Subsidiary Equity Issuance	$ (6.5)

Number of Joint Venture Investments Consolidated

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- Definition

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.31)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 27

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 20

-Article 7

+ Details

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- Details

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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- Definition

Increase in noncontrolling interest balance because of a business combination that occurred during the period.

+ References

No definition available.

+ Details

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- Definition

Amount of increase in noncontrolling interest from subsidiary issuance of equity interests to noncontrolling interest holders.

+ References

No definition available.

+ Details

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