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Retirement Plans - Defined Benefit Plan, Actual Plan Asset Allocation (Detail)	Dec. 31, 2018	Dec. 31, 2017
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

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+ References

No definition available.

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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

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