Projected Benefit Payments (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Directors Plan
Defined Benefit Plan Disclosure [Line Items]
2013	$ 83
2014	81
2015	80
2016	79
2017	111
2018 through 2022	544
Supplemental Executive Retirement Plan (SERP)
Defined Benefit Plan Disclosure [Line Items]
2013	214
2014	214
2015	214
2016	214
2017	345
2018 through 2022	$ 1,924

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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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- Definition

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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- Definition

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

+ References

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