Shareholders' Equity - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Apr. 26, 2001
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	481,791
Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Offering Date	95.00%
Common stock, authorized shares repurchase		607,754
Common stock, total shares repurchased	334,965
Schedule Of Share Based Compensation Restricted Stock and Restricted Stock Vested In Percentage	100.00%
Schedule Of Share Based Compensation Restricted Stock and Restricted Stock Grant During Period Percentage	50.00%
Schedule Of Share Based Compensation Restricted Stock and Restricted Stock Cash Credit Entitlement Percentage	50.00%
Unrecognized Stock Expenses In Restricted Stock	$ 101
Bank [Member]
Retained Earnings, Unappropriated	$ 26,000
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	500,000

Schedule Of Share based Compensation Restricted Stock And Restricted Stock Cash Credit Entitlement Percentage

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- Definition

Schedule Of Share based Compensation Restricted Stock And Restricted Stock Grant During Period Percentage

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- Definition

Schedule Of Share based Compensation Restricted Stock And Restricted Stock Vested In Percentage

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- Definition

Stock Repurchase Program, Cumulative Number of Shares Repurchased

+ References

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- Definition

The Unrecognized expense associated with the restricted stock grants and cash entitlements.

+ References

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- Definition

A segregation of retained earnings which is available for dividend distribution. Earnings not paid out as dividends but instead reinvested in the core business or used to pay off debt. Unappropriated profit is part of shareholder equity. Also called cumulative distributions or earned surplus or accumulated earnings or unappropriated profit.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 24

-Subparagraph a(4)

-Article 7

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 31

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.30(a)(3)(ii))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.23(4))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

The discount rate from market value on offering date that participants pay for shares.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

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