Schedule of Health Care Cost Trends (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Compensation And Retirement Disclosure [Abstract]
Effect of 1% increase in health-care cost trend rates, Postretirement benefit obligation	$ 0.5	$ 1.5
Effect of 1% increase in health-care cost trend rates, Total of service cost and interest cost component	0.0	0.1
Effect of 1% decrease in health-care cost trend rates, Postretirement benefit obligation	(0.5)	(1.3)
Effect of 1% decrease in health-care cost trend rates, Total of service cost and interest cost component	$ 0.0	$ (0.1)

No definition available.

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- Definition

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ 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 (m)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

+ Details

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- Definition

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

+ Details

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ References

+ Details

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

+ Details

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