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Postretirement and Other Benefits - Target Allocations (Details) - Pension Benefits	Dec. 31, 2021	Dec. 31, 2020
U.S.
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations	100.00%	100.00%
U.S. | Cash and cash equivalents
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations	1.00%	1.00%
U.S. | Domestic large cap
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations	2.00%	2.00%
U.S. | Domestic small cap
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations	1.00%	1.00%
U.S. | International
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations	6.00%	6.00%
U.S. | Fixed income securities
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations	90.00%	90.00%
U.S. | Alternative investments
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations	0.00%	0.00%
France
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations	100.00%	100.00%
France | Cash and cash equivalents
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations	11.00%	36.00%
France | Domestic large cap
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations	16.00%	30.00%
France | Domestic small cap
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations	0.00%	0.00%
France | International
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations	0.00%	0.00%
France | Fixed income securities
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations	67.00%	32.00%
France | Alternative investments
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations	6.00%	2.00%
U.K.
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations	100.00%	0.00%
U.K. | Cash and cash equivalents
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations	1.00%	0.00%
U.K. | Domestic large cap
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations	0.00%	0.00%
U.K. | Domestic small cap
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations	0.00%	0.00%
U.K. | International
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations	10.00%	0.00%
U.K. | Fixed income securities
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations	87.00%	0.00%
U.K. | Alternative investments
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations	2.00%	0.00%

X

- Definition

Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

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- Definition

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+ References

No definition available.

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