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Retirement Plans - Defined Benefit Plan, Actual Plan Asset Allocation (Detail) | Dec. 31, 2018 | Dec. 31, 2017
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United States [Member] | Pension Plans [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total defined benefit plan asset allocation |  | 100.00%
United States [Member] | Retiree Healthcare Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total defined benefit plan asset allocation | 100.00% | 100.00%
United States [Member] | Equity Securities [Member] | Pension Plans [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total defined benefit plan asset allocation |  | 77.00%
United States [Member] | Equity Securities [Member] | Retiree Healthcare Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total defined benefit plan asset allocation | 61.00% | 65.00%
United States [Member] | Debt Securities [Member] | Pension Plans [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total defined benefit plan asset allocation |  | 23.00%
United States [Member] | Debt Securities [Member] | Retiree Healthcare Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total defined benefit plan asset allocation | 39.00% | 35.00%
United States [Member] | Cash and Cash Equivalents [Member] | Pension Plans [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total defined benefit plan asset allocation |  | 0.00%
United States [Member] | Cash and Cash Equivalents [Member] | Retiree Healthcare Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total defined benefit plan asset allocation | 0.00% | 0.00%
United States [Member] | Insurance Contracts And Other [Member] | Pension Plans [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total defined benefit plan asset allocation |  | 0.00%
United States [Member] | Insurance Contracts And Other [Member] | Retiree Healthcare Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total defined benefit plan asset allocation | 0.00% | 0.00%
Non-U.S. Pension Plans [Member] | Pension Plans [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total defined benefit plan asset allocation | 100.00% | 100.00%
Non-U.S. Pension Plans [Member] | Equity Securities [Member] | Pension Plans [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total defined benefit plan asset allocation | 7.00% | 7.00%
Non-U.S. Pension Plans [Member] | Debt Securities [Member] | Pension Plans [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total defined benefit plan asset allocation | 18.00% | 16.00%
Non-U.S. Pension Plans [Member] | Cash and Cash Equivalents [Member] | Pension Plans [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total defined benefit plan asset allocation | 5.00% | 8.00%
Non-U.S. Pension Plans [Member] | Insurance Contracts And Other [Member] | Pension Plans [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total defined benefit plan asset allocation | 70.00% | 69.00%

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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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=108410482&loc=d3e1928-114920 + Details
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