Employee Benefit Plans Defined Benefit Plan Narrative (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year	$ 1.5
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan, Estimated Future Employer Contributions
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year	3.5
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan, Estimated Future Employer Contributions
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year	$ 0.1
Defined Benefit Plan, Plan Participants, Pre-65 [Member]
Defined Benefit Plan, Assumed Health Care Cost Trend Rates
Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year	8.00%
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate	5.00%
Defined Benefit Plan, Year that Rate Reaches Ultimate Trend Rate	2022
Defined Benefit Plan, Plan Participants, Post-65 [Member]
Defined Benefit Plan, Assumed Health Care Cost Trend Rates
Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year	7.50%
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate	5.00%
Defined Benefit Plan, Year that Rate Reaches Ultimate Trend Rate	2020

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Amount included in accumulated other comprehensive income (AOCI) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position, including gain (loss), prior service cost (credit), and transition asset (obligation).

+ References

No definition available.

+ Details

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- Definition

The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ 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 (l)

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Health Care Cost Trend Rate

-URI http://asc.fasb.org/extlink&oid=6514820

+ 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.

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- Definition

The ultimate trend rate for health care costs.

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- Definition

Year the ultimate health care cost trend rate is expected to be reached, in CCYY format.

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