Employee Benefit Plans - Additional Information (Detail) $ in Millions	9 Months Ended
Sep. 30, 2016 USD ($)
Compensation and Retirement Disclosure [Abstract]
Cash contributions made for defined benefit pension benefit plans	$ 17
Cash contributions made for postretirement benefit plans	2
Expected additional cash contributions	$ 2

No definition available.

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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan in the current remaining fiscal period.

+ References

No definition available.

+ Details

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- Definition

The amount of cash or cash equivalents contributed during the reporting period by the entity to fund non-pension postretirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585

+ Details

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- Definition

The amount of cash or cash equivalents contributed by the entity to fund its pension plans.

+ References

+ Details

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