Summary of Activity in Plans (Detail) (USD $)	12 Months Ended
Dec. 31, 2012
Number Outstanding
Outstanding, beginning of period	227,075
Forfeited or expired	(51,897)
Outstanding, end of period	175,178
Vested or expected to vest	164,178
Exercisable at end of period	134,178
Weighted Average Exercise Price
Outstanding, beginning of period	$ 6.63
Forfeited or expired	$ 8.00
Outstanding, end of period	$ 6.23
Vested or expected to vest	$ 6.24
Exercisable at end of period	$ 6.53
1996 and 2008 LTIP
Number Outstanding
Outstanding, beginning of period	222,793
Forfeited or expired	(49,043)
Outstanding, end of period	173,750
Vested or expected to vest	162,750
Exercisable at end of period	132,750
Weighted Average Exercise Price
Outstanding, beginning of period	$ 6.57
Forfeited or expired	$ 7.91
Outstanding, end of period	$ 6.19
Vested or expected to vest	$ 6.20
Exercisable at end of period	$ 6.48
Stock Option Plan
Number Outstanding
Outstanding, beginning of period	4,282
Forfeited or expired	(2,854)
Outstanding, end of period	1,428
Vested or expected to vest	1,428
Exercisable at end of period	1,428
Weighted Average Exercise Price
Outstanding, beginning of period	$ 9.91
Forfeited or expired	$ 9.61
Outstanding, end of period	$ 10.49
Vested or expected to vest	$ 10.49
Exercisable at end of period	$ 10.49

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 718

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-Section 50

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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As of the balance sheet date, the weighted-average exercise price (at which grantees can acquire the shares reserved for issuance) for exercisable stock options that are fully vested or expected to vest.

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