Pension and Postretirement Benefit Plans - Pension Asset Fair Value Level 3 (Details) - Qualified and Non-qualified Pension Benefits - International - Funded - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Benefit Plan Information
Foreign currency exchange	$ (376.0)	$ (80.0)
Level 3
Benefit Plan Information
Defined benefit plan increase/decrease related to currency exchange rates	43.5	(7.0)
Defined benefit plan increase/decrease related to aggregate of net purchases and net unrealized gains and losses	(0.5)	24.0
Defined benefit plan increase/decrease related to Level 3 assets	$ 43.0	$ 17.0

The defined benefit plan increase/decrease related to Level 3 assets.

No definition available.

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- Definition

The defined benefit plan increase/decrease related to aggregate of net purchases and net unrealized gains and losses.

+ References

No definition available.

+ Details

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- Definition

The defined benefit plan increase/decrease related to currency exchange rates.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) plan assets of defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

+ 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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