Employee Benefit Plans (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014 Age
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Benefit determination period for pension plan	5 years
Defined benefit plan, non-contributory, retirement age requirement	62
Defined benefit plan, contributory, retirement age requirement	62
Pension Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Expected employer contributions in next fiscal year	1.7
Postretirement health and life plans [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Expected employer contributions in next fiscal year	0.9
Minimum [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan, contributory, employee contribution percentage	25.00%
Maximum [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan, contributory, employee contribution percentage	100.00%

Benefit Determination Period for Pension Plan

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- Definition

Defined Benefit Plan, Contributory, Employee Contribution Percentage

+ References

No definition available.

+ Details

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- Definition

Defined Benefit Plan, Contributory, Retirement Age Requirement

+ References

No definition available.

+ Details

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- Definition

Defined Benefit Plan, Non-contributory, Retirement Age Requirement

+ References

No definition available.

+ 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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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