Note 13 - Share-Based Compensation (Detail) - Summary of Option Transactions (USD $)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Outstanding	614,917	671,500	699,790
Outstanding (in Dollars per share)	$ 11.24	$ 10.66	$ 10.29
Granted	194,223	211,631
Granted (in Dollars per share)	$ 12.62	$ 11.43
Exercised	(138,252)	(117,846)
Exercised (in Dollars per share)	$ 9.32	$ 8.97
Lapsed	(86,400)	(93,025)
Lapsed (in Dollars per share)	$ 12.57	$ 11.65
Cancelled	(26,154)	(29,050)
Cancelled (in Dollars per share)	$ 12.37	$ 10.84

Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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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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Gross number of share options (or share units) granted during the period.

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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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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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