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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- Definition

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

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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Note 6 - Stock-Based Compensation (Detail) - Stock Options Outstanding (USD $)	3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012	Dec. 31, 2011
Weighted-Average Exercise Price (in Shares)	592,497	652,064	773,273	831,393
Weighted-Average Remaining Contractual Life	$ 11.26	$ 11.12	$ 10.94	$ 11.19
Weighted-Average Remaining Contractual Life	3 years 248 days
Exercise Price Range 1 [Member]
Exercise Price	$ 6.34
Exercise Price	$ 7.45
Weighted-Average Exercise Price (in Shares)	238,008
Weighted-Average Remaining Contractual Life	$ 6.38
Weighted-Average Remaining Contractual Life	5 years 197 days
Exercise Price Range 2 [Member]
Exercise Price	$ 7.46
Exercise Price	$ 10.63
Weighted-Average Exercise Price (in Shares)	115,151
Weighted-Average Remaining Contractual Life	$ 9.53
Weighted-Average Remaining Contractual Life	299 days
Exercise Price Range 3 [Member]
Exercise Price	$ 10.64
Exercise Price	$ 13.87
Weighted-Average Exercise Price (in Shares)	118,582
Weighted-Average Remaining Contractual Life	$ 11.40
Weighted-Average Remaining Contractual Life	3 years 105 days
Exercise Price Range 4 [Member]
Exercise Price	$ 13.88
Exercise Price	$ 26.86
Weighted-Average Exercise Price (in Shares)	120,756
Weighted-Average Remaining Contractual Life	$ 22.39
Weighted-Average Remaining Contractual Life	3 years 47 days