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Post-Employment and Other Long-Term Employees Benefits - Pension Plan Asset Allocation (Detail) | Dec. 31, 2016 | Dec. 31, 2015
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Allocation of pension plan assets | 100.00% | 100.00%
Cash and Cash Equivalents [Member] |  |
Allocation of pension plan assets | 2.00% | 3.00%
Equity Securities [Member] |  |
Allocation of pension plan assets | 29.00% | 27.00%
Government Debt Securities [Member] |  |
Allocation of pension plan assets | 3.00% | 2.00%
Corporate Debt Securities [Member] |  |
Allocation of pension plan assets | 26.00% | 26.00%
Investment Funds [Member] |  |
Allocation of pension plan assets | 18.00% | 19.00%
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 | 20.00% | 21.00%

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- Definition Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2446-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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