Schedule Of Expected Benefit Payments (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Pension
Defined Benefit Plan Disclosure [Line Items]
2013	$ 19,589
2014	21,126
2015	23,028
2016	24,892
2017	26,631
Years 2018 - 2022	156,728
Postretirement Benefit
Defined Benefit Plan Disclosure [Line Items]
2013	3,980
2014	2,820
2015	2,866
2016	2,816
2017	2,718
Years 2018 - 2022	$ 11,604

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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.

+ 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=21915506&loc=d3e1928-114920

+ Details

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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.

+ References

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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.

+ References

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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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