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Post-Employment and Other Long-Term Employees Benefits - Pension Plan Asset Allocation (Detail) | Dec. 31, 2020 | Dec. 31, 2019
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Allocation of pension plan assets | 100.00% | 100.00%
Cash and Cash Equivalents [Member] |  |
Allocation of pension plan assets | 1.00% | 1.00%
Equity Securities [Member] |  |
Allocation of pension plan assets | 23.00% | 24.00%
Government Debt Securities [Member] |  |
Allocation of pension plan assets | 12.00% | 12.00%
Corporate Debt Securities [Member] |  |
Allocation of pension plan assets | 15.00% | 16.00%
Investment Funds [Member] |  |
Allocation of pension plan assets | 21.00% | 21.00%
Real Estate [Member] |  |
Allocation of pension plan assets | 2.00% | 2.00%
Other (Mainly Insurance Assets - Contracts and Reserves) [Member] |  |
Allocation of pension plan assets | 26.00% | 24.00%

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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=118255775&loc=d3e1928-114920 + Details
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