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

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921

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

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- 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=118255775&loc=d3e1928-114920

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Postretirement and Other Benefits - Target Allocations (Details) - Pension Benefits	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
United States
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations		100.00%	100.00%
United States \| Cash and cash equivalents
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations		1.00%	1.00%
United States \| Domestic large cap
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations		5.00%	5.00%
United States \| Domestic small cap
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations		3.00%	3.00%
United States \| International
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations		15.00%	14.00%
United States \| Fixed income securities
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations		76.00%	77.00%
United States \| 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		41.00%	43.00%
France \| Domestic large cap
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations		31.00%	28.00%
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		26.00%	27.00%
France \| Alternative investments
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actual allocations		2.00%	2.00%
Forecast \| United States
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations 2019	100.00%
Forecast \| United States \| Cash and cash equivalents
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations 2019	0.00%
Forecast \| United States \| Domestic large cap
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations 2019	9.00%
Forecast \| United States \| Domestic small cap
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations 2019	5.00%
Forecast \| United States \| International
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations 2019	10.00%
Forecast \| United States \| Fixed income securities
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations 2019	76.00%
Forecast \| United States \| Alternative investments
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations 2019	0.00%