Market capitalization of investments.

No definition available.

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- Definition

Remeasurement (gain) loss, net, on pension plans

+ References

No definition available.

+ Details

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- Details

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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position.

+ References

+ Details

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- Definition

Target allocation maximum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ 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)(i)

-URI http://asc.fasb.org/extlink&oid=28361610&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)(i)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e2446-114920

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- Definition

Target allocation minimum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ References

+ Details

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- Details

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- Details

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- Details

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- Details

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Employee Benefit Plans (Narrative) (Details) (USD $)	3 Months Ended			12 Months Ended
Employee Benefit Plans (Narrative) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Mark-to-market actuarial net losses (gains)	$ 56,500,000	$ (44,000,000)	$ 42,000,000
Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of equity securities, minimum				60.00%
Percentage of equity securities, maximum				70.00%
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of equity securities, minimum				30.00%
Percentage of equity securities, maximum				40.00%
Alternative Investments and Cash [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of equity securities, minimum				0.00%
Percentage of equity securities, maximum				10.00%
Large-cap equity \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Market capitalization	10,000,000,000			10,000,000,000
Small-cap equity \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Market capitalization	2,000,000,000			2,000,000,000
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Mark-to-market actuarial net losses (gains)				55,200,000	(43,000,000)	44,000,000
Employer contributions to defined benefit plans				24,500,000
Health Care Benefits
Defined Benefit Plan Disclosure [Line Items]
Mark-to-market actuarial net losses (gains)				1,300,000	(1,000,000)	(2,000,000)
Employer contributions to defined benefit plans				1,600,000