Share-based Compensation Awards (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Stock-settled awards
Stock-based Payment Award
Awards granted	1.1	0.9	0.8
Weighted-average grant-date fair value (per award)	$ 13.51	$ 11.43	$ 11.94
Total fair value of vested awards distributed	$ 35.4	$ 63.5	$ 63.1
Accrued dividends on non-vested stock-settled awards	0.7	1.1
Dividends paid for stock-settled awards	1.5	1.7
Cash-settled awards
Stock-based Payment Award
Awards granted	0.1	0.1	0
Weighted-average grant-date fair value (per award)	$ 16.35	$ 10.94	$ 8.96
Total fair value of vested awards distributed	5.4	11.1	10.4
Performance-based awards
Stock-based Payment Award
Awards granted	1.5	1.8	1.8
Weighted-average grant-date fair value (per award)	$ 11.97	$ 10.61	$ 11.58
Total fair value of vested awards distributed	$ 17.7	$ 11.5	$ 30.8

Dividends paid for stock-settled awards vested during the period.

No definition available.

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- Definition

Amount of paid and unpaid stock dividends declared and applicable to holders of share-based compensation, for example, but not limited to, non-vested shares, stock options, or restricted stock units.

+ References

No definition available.

+ Details

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

+ Details

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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