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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

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

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph A240

-Subparagraph b(1)(c), d(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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Data Type:	xbrli:sharesItemType
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- Definition

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

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

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

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.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(b)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

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

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-Topic 718

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-Section 50

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-Name Statement of Financial Accounting Standard (FAS)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)

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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.

+ References

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Note 7 - Shareholders' Equity (Detail) - Information about stock options outstanding (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Range of Exercise Prices, Options Outstanding, Number (in Shares)	2,211,488	2,356,228	1,794,694
Range of Exercise Prices, Options Outstanding, Weighted- Average Remaining Contractual Life	4 years 310 days
Range of Exercise Prices, Options Outstanding, Weighted- Average Exercise Price	$ 7.47	$ 8.34	$ 9.71
Range of Exercise Prices, Options Exercisable, Number (in Shares)	1,013,098	989,972
Range of Exercise Prices, Options Exercisable, Weighted- Average Exercise Price	$ 7.64	$ 9.62
$ 3.22-$ 3.91 [Member]
Range of Exercise Prices, Options Outstanding, Number (in Shares)	310,750
Range of Exercise Prices, Options Outstanding, Weighted- Average Remaining Contractual Life	5 years 62 days
Range of Exercise Prices, Options Outstanding, Weighted- Average Exercise Price	$ 3.59
Range of Exercise Prices, Options Exercisable, Number (in Shares)	170,000
Range of Exercise Prices, Options Exercisable, Weighted- Average Exercise Price	$ 3.91
$ 3.92-$ 4.41 [Member]
Range of Exercise Prices, Options Outstanding, Number (in Shares)	262,750
Range of Exercise Prices, Options Outstanding, Weighted- Average Remaining Contractual Life	5 years 6 months
Range of Exercise Prices, Options Outstanding, Weighted- Average Exercise Price	$ 4.18
Range of Exercise Prices, Options Exercisable, Number (in Shares)	70,502
Range of Exercise Prices, Options Exercisable, Weighted- Average Exercise Price	$ 4.41
$ 4.42-$ 4.42 [Member]
Range of Exercise Prices, Options Outstanding, Number (in Shares)	310,000
Range of Exercise Prices, Options Outstanding, Weighted- Average Remaining Contractual Life	5 years 343 days
Range of Exercise Prices, Options Outstanding, Weighted- Average Exercise Price	$ 4.42
Range of Exercise Prices, Options Exercisable, Number (in Shares)	103,336
Range of Exercise Prices, Options Exercisable, Weighted- Average Exercise Price	$ 4.42
$ 4.43-$ 6.37 [Member]
Range of Exercise Prices, Options Outstanding, Number (in Shares)	93,600
Range of Exercise Prices, Options Outstanding, Weighted- Average Remaining Contractual Life	4 years 9 months
Range of Exercise Prices, Options Outstanding, Weighted- Average Exercise Price	$ 5.24
Range of Exercise Prices, Options Exercisable, Number (in Shares)	44,203
Range of Exercise Prices, Options Exercisable, Weighted- Average Exercise Price	$ 5.17
$ 6.38-$ 6.42 [Member]
Range of Exercise Prices, Options Outstanding, Number (in Shares)	300,000
Range of Exercise Prices, Options Outstanding, Weighted- Average Remaining Contractual Life	5 years
Range of Exercise Prices, Options Outstanding, Weighted- Average Exercise Price	$ 6.42
Range of Exercise Prices, Options Exercisable, Number (in Shares)	150,000
Range of Exercise Prices, Options Exercisable, Weighted- Average Exercise Price	$ 6.42
$ 6.43-$ 9.70 [Member]
Range of Exercise Prices, Options Outstanding, Number (in Shares)	184,166
Range of Exercise Prices, Options Outstanding, Weighted- Average Remaining Contractual Life	4 years 109 days
Range of Exercise Prices, Options Outstanding, Weighted- Average Exercise Price	$ 7.29
Range of Exercise Prices, Options Exercisable, Number (in Shares)	124,835
Range of Exercise Prices, Options Exercisable, Weighted- Average Exercise Price	$ 7.54
$ 9.71-$12.00 [Member]
Range of Exercise Prices, Options Outstanding, Number (in Shares)	419,722
Range of Exercise Prices, Options Outstanding, Weighted- Average Remaining Contractual Life	3 years 229 days
Range of Exercise Prices, Options Outstanding, Weighted- Average Exercise Price	$ 10.62
Range of Exercise Prices, Options Exercisable, Number (in Shares)	219,722
Range of Exercise Prices, Options Exercisable, Weighted- Average Exercise Price	$ 11.19
$ 12.85-$12.96 [Member]
Range of Exercise Prices, Options Outstanding, Number (in Shares)	69,000
Range of Exercise Prices, Options Outstanding, Weighted- Average Remaining Contractual Life	138 days
Range of Exercise Prices, Options Outstanding, Weighted- Average Exercise Price	$ 12.93
Range of Exercise Prices, Options Exercisable, Number (in Shares)	69,000
Range of Exercise Prices, Options Exercisable, Weighted- Average Exercise Price	$ 12.93
$ 12.97-$13.48 [Member]
Range of Exercise Prices, Options Outstanding, Number (in Shares)	61,500
Range of Exercise Prices, Options Outstanding, Weighted- Average Remaining Contractual Life	2 years 54 days
Range of Exercise Prices, Options Outstanding, Weighted- Average Exercise Price	$ 13.34
Range of Exercise Prices, Options Exercisable, Number (in Shares)	61,500
Range of Exercise Prices, Options Exercisable, Weighted- Average Exercise Price	$ 13.34
$ 13.49-$15.00 [Member]
Range of Exercise Prices, Options Outstanding, Number (in Shares)	200,000
Range of Exercise Prices, Options Outstanding, Weighted- Average Remaining Contractual Life	7 years 14 days
Range of Exercise Prices, Options Outstanding, Weighted- Average Exercise Price	$ 15.00
Range of Exercise Prices, Options Exercisable, Weighted- Average Exercise Price	$ 0.00
$ 3.22-$15.00 [Member]
Range of Exercise Prices, Options Outstanding, Number (in Shares)	2,211,488
Range of Exercise Prices, Options Outstanding, Weighted- Average Remaining Contractual Life	4 years 310 days
Range of Exercise Prices, Options Outstanding, Weighted- Average Exercise Price	$ 7.47
Range of Exercise Prices, Options Exercisable, Number (in Shares)	1,013,098
Range of Exercise Prices, Options Exercisable, Weighted- Average Exercise Price	$ 7.64