Employee Benefit Plans - Company's Projected Benefit Payments (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013
Retirement Plans [Member]
2014	$ 85,789
2015	86,449
2016	84,736
2017	87,218
2018	89,752
2019-2023	484,517
Retiree Health and Life Insurance Plans [Member]
2014	2,845
2015	3,014
2016	2,987
2017	2,885
2018	2,759
2019-2023	$ 10,858

Amount of benefits expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year from a defined benefit plan.

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=28361610&loc=d3e1928-114920

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- Definition

Amount of benefits expected to be paid in the next fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the fifth fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the fourth fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the third fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the second fiscal year following the latest fiscal year from a defined benefit plan.

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