Pensions and Other Postretirement Benefits - Effect of One-Percentage-Point Change in Assumed Health Care Trend Rates (Details) - Posretirement Benefits $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($)
Health Care Trend Rate Sensitivity:
Effect on total interest and service cost components, one-percentage-point increase	$ 0.1
Effect on total interest and service cost components, one-percentage-point decrease	(0.1)
Effect on year-end postretirement benefit obligation, one-percentage-point increase	2.1
Effect on year-end postretirement benefit obligation, one-percentage-point decrease	$ (1.8)

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- Definition

Amount of decrease in accumulated postretirement benefit obligation from one-percentage-point decrease in assumed health care cost trend rate.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (m)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- Definition

Amount of decrease in service and interest cost components of net periodic postretirement benefit cost from one-percentage-point decrease in assumed health care cost trend rate.

+ References

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- Definition

Amount of increase in accumulated postretirement benefit obligation from one-percentage-point increase in assumed health care cost trend rate.

+ References

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Amount of increase in service and interest cost components of net periodic postretirement benefit cost from one-percentage-point increase in assumed health care cost trend rate.

+ References

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