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Long-Term Employee Benefit Liabilities - Schedule of Company's Defined Benefit Pension Plans (Parenthetical) (Detail) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2017 | Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit pension, non cash settlement |  |  | $ 13
Pension Plan, Defined Benefit [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employer contributions |  | $ 82 | 19
Defined benefit pension plan assets, settlement |  |  | $ 32
Target allocation in 2018 | 100.00% | 100.00% |
Asset allocation of defined benefit pension plans | 100.00% | 100.00% |
U.S. Defined Benefit Pension Plans [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employer contributions | $ 60 |  |
Equity Investments [Member] | Pension Plan, Defined Benefit [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Asset allocation of defined benefit pension plans | 50.00% | 50.00% |
Equity Investments [Member] | Pension Plan, Defined Benefit [Member] | Minimum [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Target allocation in 2018 | 55.00% | 55.00% |
Equity Investments [Member] | Pension Plan, Defined Benefit [Member] | Maximum [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Target allocation in 2018 | 75.00% | 75.00% |
Fixed Income Securities [Member] | Pension Plan, Defined Benefit [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Asset allocation of defined benefit pension plans | 35.00% | 35.00% |
Fixed Income Securities [Member] | Pension Plan, Defined Benefit [Member] | Minimum [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Target allocation in 2018 | 25.00% | 25.00% |
Fixed Income Securities [Member] | Pension Plan, Defined Benefit [Member] | Maximum [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Target allocation in 2018 | 45.00% | 45.00% |
Cash and Cash Equivalents [Member] | Pension Plan, Defined Benefit [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Asset allocation of defined benefit pension plans | 15.00% | 15.00% |
Cash and Cash Equivalents [Member] | Pension Plan, Defined Benefit [Member] | Minimum [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Target allocation in 2018 | 0.00% | 0.00% |
Cash and Cash Equivalents [Member] | Pension Plan, Defined Benefit [Member] | Maximum [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Target allocation in 2018 | 15.00% | 15.00% |

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- Definition Amount of contribution received by defined benefit plan from employer which increases plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(ii) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2709-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(iv)(01) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(i) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of payment, which decreases plan assets of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(ii) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 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)(5)(iv)(01) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(8) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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