Basis of Presentation - Additional Information (Detail) $ in Millions	3 Months Ended
Mar. 31, 2017 USD ($)
ASU 2017-07 Not Yet Adopted, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost
Basis Of Presentation [Line Items]
Increase in operating income	$ 9
Increase in other expense (income), net	9
ASU 2016-09, Improvements to Employee Share-Based Payment Accounting
Basis Of Presentation [Line Items]
Increase in net income	17
Increase in operating cash flow	17
Windfall tax benefits	$ 15

Amount of the effect of a change in accounting principle on operating profit or loss.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22499-107794

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22580-107794

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22583-107794

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