Pension and Other Post-Retirement Benefit Plans - Schedule of Impact of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Compensation and Retirement Disclosure [Abstract]
Increase to total of service and interest cost components, One-Percent-Point-Increase	$ 16	$ 10	$ 13
Decrease to total of service and interest cost components, One-Percentage-Point-Decrease	(18)	(11)	(14)
Increase to post-retirement benefit obligation, One-Percentage-Point-Increase	181	268	228
Decrease to post-retirement benefit obligation, One-Percentage-Point-Decrease	$ (190)	$ (278)	$ (229)

No definition available.

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- Definition

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.

+ References

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=65897934&loc=d3e1928-114920

+ Details

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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

+ Details

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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

+ Details

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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.

+ References

+ Details

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