Pension and Other Postretirement Benefits - Benefits Expected to be Paid in Subsequent Years from Our Pension and Other Postretirement as Well as Medicare Subsidy Receipts (Detail) $ in Thousands	Dec. 31, 2016 USD ($)
Pension Benefits [Member]
Pension And Other Employee Benefit Plans [Line Items]
2017	$ 15,785
2018	16,119
2019	16,873
2020	17,145
2021	16,176
2022-2026	79,935
Total	162,033
Other Benefits [Member]
Pension And Other Employee Benefit Plans [Line Items]
2017	1,811
2018	1,763
2019	1,706
2020	1,672
2021	1,636
2022-2026	8,016
Total	$ 16,604

Defined Benefit Plan Expected Future Benefit Payments In Next Ten Years

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- Definition

Pension And Other Employee Benefit Plans [Line Items]

+ References

No definition available.

+ Details

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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

+ Details

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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+ Details

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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+ Details

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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