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Postretirement and Other Benefits - Target Allocations (Details) - Pension Benefits | Dec. 31, 2021 | Dec. 31, 2020
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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%

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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=123447040&loc=d3e1928-114920 + Details
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