Defined Contribution Plans, Pension and Other Post-Retirement Benefit Plans - Impact of Differences in Ultimate Health Care Cost Trend Rates (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2015 USD ($)
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
1 Percentage point increase in health care cost trend rates, other post-retirement benefit expense	$ 2
1 Percentage point increase in health care cost trend rates, other post-retirement benefit liability	8
1 Percentage point decrease in health care cost trend rates, other post-retirement benefit expense	(2)
1 Percentage point decrease in health care cost trend rates, other post-retirement benefit liability	$ (8)

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (m)
-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ References

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

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- References

No definition available.

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