Note 7 - Commitments and Contingencies (Detail) - Lifetime Lube, Oil and Filter Contracts Sold (Self-insured Lifetime Oil Contracts [Member], USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Self-insured Lifetime Oil Contracts [Member]
2013	$ 8,448
2014	5,839
2015	4,541
2016	3,547
2017	2,827
Thereafter	8,721
Total	$ 33,923

Amount of deferred revenue to be recognized in the next fiscal year following the latest fiscal year

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Amount of deferred revenue to be recognized in the fifth year following the latest fiscal year

+ References

No definition available.

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Amount of deferred revenue to be recognized in the fourth year following the latest fiscal year

+ References

No definition available.

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Amount of deferred revenue to be recognized in the third year following the latest fiscal year

+ References

No definition available.

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Amount of deferred revenue to be recognized in the second year following the latest fiscal year

+ References

No definition available.

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Amount of deferred revenue to be recognized after the fifth year following the latest fiscal year

+ References

No definition available.

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Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 13.A.4(a).Q1 Response)

-URI http://asc.fasb.org/extlink&oid=6600647&loc=d3e214044-122780

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 13

-Section A

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