Pension and Other Postretirement Benefits - Summary of Target Asset Allocations and Major Asset Categories (Detail)	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
U.S. Pension Benefits [Member] \| Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	65.00%
Percentage of Plan Assets	47.00%	58.00%
U.S. Pension Benefits [Member] \| Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	15.00%
Percentage of Plan Assets	21.00%	19.00%
U.S. Pension Benefits [Member] \| Alternative Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	15.00%
Percentage of Plan Assets	8.00%	13.00%
U.S. Pension Benefits [Member] \| Other (Primarily Cash and Cash Equivalents) [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	5.00%
Percentage of Plan Assets	24.00%	10.00%
Foreign Pension Benefits [Member] \| Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	44.00%
Percentage of Plan Assets	48.00%	46.00%
Foreign Pension Benefits [Member] \| Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	35.00%
Percentage of Plan Assets	34.00%	33.00%
Foreign Pension Benefits [Member] \| Alternative Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	21.00%
Percentage of Plan Assets	18.00%	21.00%
Foreign Pension Benefits [Member] \| Other (Primarily Cash and Cash Equivalents) [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	0.00%
Percentage of Plan Assets	0.00%	0.00%

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- Definition

Target allocation of investments of this type to total plan assets presented on a weighted average basis.

+ 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)(i)
-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)(i)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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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

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