Note 5 - Income Taxes (Detail) - Income Tax Reconciliation (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Expected federal income taxes	$ 7,772	$ 6,356	$ 4,527
Foreign tax rate differential	(203)	(145)	(59)
U.S. tax graduated rates	11	(99)
State income taxes, net of federal benefit and state tax credits	552	522	257
Federal tax credits	(282)	(132)	(110)
Uncertain tax positions	(73)	9	72
Deferred tax adjustment due to change in state tax law	(661)		138
Other	23	85	(9)
Total	$ 7,139	$ 6,596	$ 4,816

No authoritative reference available.

No definition available.

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- Definition

The sum of the differences between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable uncertain tax positions.

+ References

No definition available.

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- Definition

The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to the difference between the graduated federal income tax rates and the highest applicable statutory income tax rate applied to domestic earnings or loss for the period.

+ References

No definition available.

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- Definition

The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (a),(b)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32639-109319

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 45

-Subparagraph a, 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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

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-Section S99

-Paragraph 1

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Article 4

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Income Tax Expense (or Benefit)

-URI http://asc.fasb.org/extlink&oid=6515339

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to total foreign income tax expense or benefit. The foreign income tax expense or benefit difference represents the income tax expense or benefit at applicable domestic statutory income tax rates applied to foreign earnings or loss for the period versus the foreign income tax expense or benefit calculated by applying the appropriate foreign tax rates.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Name Regulation S-X (SX)

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 47

-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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-Name Accounting Standards Codification

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-Publisher FASB

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Paragraph h

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The sum of other amounts reflected in the reconciliation of the statutory tax provision (benefit) to the actual tax provision (benefit).

+ References

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