Pension and Other Postretirement Benefits - Summary of Target Asset Allocations and Major Asset Categories (Detail) - Defined Benefit Pension Plan [Member]	Dec. 31, 2019	Dec. 31, 2018
Equity Securities [Member] \| U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	54.00%
Percentage of Plan Assets	45.00%	25.00%
Equity Securities [Member] \| Foreign Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	14.00%
Percentage of Plan Assets	14.00%	50.00%
Fixed Income Securities [Member] \| U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	43.00%
Percentage of Plan Assets	42.00%	45.00%
Fixed Income Securities [Member] \| Foreign Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	75.00%
Percentage of Plan Assets	75.00%	35.00%
Alternative Investments [Member] \| U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	0.00%
Percentage of Plan Assets	10.00%	10.00%
Alternative Investments [Member] \| Foreign Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	11.00%
Percentage of Plan Assets	11.00%	15.00%
Other (Primarily Cash and Cash Equivalents) [Member] \| U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	3.00%
Percentage of Plan Assets	3.00%	20.00%
Other (Primarily Cash and Cash Equivalents) [Member] \| Foreign Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	0.00%
Percentage of Plan Assets	0.00%	0.00%

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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/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-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

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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

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