Related Parties (Details) (Director [Member], USD $) In Millions, unless otherwise specified	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013
Related Party Transaction [Line Items]
Amounts Invested in Defined Contribution Plan Mutual Fund Managed by a Directors Investment Advisory Firm	$ 23.4
Amounts Invested in Defined Contribution Plan Mutual Fund Managed by a Directors Investment Advisory Firm Percentage of Total Defined Contribution Plan Investments	6.50%
Trinity [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Transaction	166.6
Related Party Transaction, Expenses from Transactions with Related Party	0.2	0.2
Pension Plan, Defined Benefit [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party	0.2	0.2
Pension Plan, Defined Benefit [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Transaction	$ 159.4

Amounts Invested in Defined Contribution Plan Mutual Fund Managed by a Director's Investment Advisory Firm

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- Definition

Amounts Invested in Defined Contribution Plan Mutual Fund Managed by a Director's Investment Advisory Frim, Percentage of Total Defined Contribution Plan Investments

+ References

No definition available.

+ Details

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- Definition

Investment Assets Managed by a Directors Investment Advisory Firm

+ References

No definition available.

+ Details

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- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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