v2.3.0.15

Related Parties (Details) (Director [Member], USD $)	3 Months Ended	9 Months Ended
	Sep. 30, 2011 Defined Benefit Pension [Member]	Sep. 30, 2011 Defined Benefit Pension [Member]	Sep. 30, 2011 Trinity [Member]	Sep. 30, 2010 Trinity [Member]	Sep. 30, 2011
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Transaction			$ 101,200,000
Related Party Transaction, Expenses from Transactions with Related Party	0.1	200,000	200,000	100,000
Related Party Transaction Amount of Assets Under Management in Defined Benefit Plans					95,100,000
Related Party Transaction Amount of Assets in Defined Contributions Plans					$ 17,000,000
Related Party Transaction Percent of Assets in Defined Contribution Plan Assets					6.30%

X

- Definition

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

+ Details

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- Definition

Investment Assets Managed by a Directors Investment Advisory Firm

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X

- Definition

Related Party Transaction Amount of Assets Under Management in Defined Benefit Plans

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- Definition

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

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 57

-Paragraph 2

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 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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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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