Employee Benefit Plans (Details 3) (USD $) In Millions, unless otherwise specified	12 Months Ended		12 Months Ended
Dec. 31, 2013 Commingled Global Fund Allocations item	Dec. 31, 2013 Significant Unobservable Inputs (Level 3)	Dec. 31, 2012 Significant Unobservable Inputs (Level 3)	Dec. 31, 2013 Significant Unobservable Inputs (Level 3) Global Equity Common Trust Funds	Dec. 31, 2012 Significant Unobservable Inputs (Level 3) Global Equity Common Trust Funds	Dec. 31, 2013 Significant Unobservable Inputs (Level 3) Commingled Global Fund Allocations	Dec. 31, 2012 Significant Unobservable Inputs (Level 3) Commingled Global Fund Allocations	Dec. 31, 2013 Significant Unobservable Inputs (Level 3) Fixed Income Common Trust Funds	Dec. 31, 2011 Significant Unobservable Inputs (Level 3) Fixed Income Common Trust Funds	Dec. 31, 2013 Significant Unobservable Inputs (Level 3) Other	Dec. 31, 2012 Significant Unobservable Inputs (Level 3) Other
Changes in the fair value of Level 3 assets
Fair value of plan assets - beginning of year		$ 193.4	$ 161.7	$ 29.0	$ 24.4	$ 155.6	$ 129.9	$ 1.4	$ 1.4	$ 7.4	$ 6.0
Transfers from Level 3 to Level 2 assets		(105.6)				(105.6)
Realized gains		0.9	0.1			0.9					0.1
Unrealized gains (losses) relating to instruments still held at period end		0.3	16.5	0.4	1.8		12.7			(0.1)	2.0
Purchases		3.1	15.8	3.1	2.8		13.0
Sales		(78.9)	(0.7)	(25.7)		(50.9)		(1.4)		(0.9)	(0.7)
Fair value of plan assets - end of year		$ 13.2	$ 193.4	$ 6.8	$ 29.0		$ 155.6		$ 1.4	$ 6.4	$ 7.4
Number of funds transferred from level 3 to level 2	1

The increase in plan assets attributed to the purchase of additional investments.

No definition available.

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- Definition

The decrease in plan assets attributed to the sale of investments.

+ References

No definition available.

+ Details

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- Definition

Represents the number of funds transferred from level 3 to level 2.

+ References

No definition available.

+ Details

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- Definition

Actual return on plan assets, separately identifying the amount related to assets sold during the period.

+ References

+ Details

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- Definition

Actual return on plan assets, separately identifying the amount related to assets still held at the reporting date.

+ References

+ Details

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- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph d(iv)(b)(i)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Section 35

-Paragraph 50

-URI http://asc.fasb.org/extlink&oid=6867990&loc=d3e12355-114930

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 87

-Paragraph 49

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Transfers in and out of Level 3. For example, transfers due to changes in the observability of significant inputs.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(iv)(02)(C)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)(iv)(02)(C)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e2446-114920

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph d(iv)(b)(iii)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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