Note 3 - Acquisitions (Detail) - Preliminary Allocation of Purchase Price (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Premex Group [Member] \| Preliminary Purchase Price Allocation [Member] \| Customer Relationships [Member]
Intangible assets	$ 32,886	$ 32,886
Premex Group [Member] \| Preliminary Purchase Price Allocation [Member] \| Trade Names [Member]
Intangible assets	10,602	10,602
Premex Group [Member] \| Preliminary Purchase Price Allocation [Member] \| Noncompete Agreements [Member]
Intangible assets	109	109
Premex Group [Member] \| Preliminary Purchase Price Allocation [Member] \| Unpatented Technology [Member]
Intangible assets	2,356	2,356
Premex Group [Member] \| Preliminary Purchase Price Allocation [Member]
Goodwill	28,294	28,131
Deferred tax asset (liability) associated with step-up in book basis	603	603
Assets acquired and liabilities assumed, net	32,856	33,019
Totals	108,356	108,356
Premex Group [Member] \| Purchase Price Adjustments and Reclassifications [Member]
Goodwill	163
Assets acquired and liabilities assumed, net	(163)
Premex Group [Member]
Totals		108,400
Other 2011 Acquisitions [Member] \| Preliminary Purchase Price Allocation [Member] \| Customer Relationships [Member]
Intangible assets	18,577	18,577
Other 2011 Acquisitions [Member] \| Preliminary Purchase Price Allocation [Member] \| Trade Names [Member]
Intangible assets	2,989	2,989
Other 2011 Acquisitions [Member] \| Preliminary Purchase Price Allocation [Member] \| Noncompete Agreements [Member]
Intangible assets	197	197
Other 2011 Acquisitions [Member] \| Preliminary Purchase Price Allocation [Member] \| Unpatented Technology [Member]
Intangible assets	334	334
Other 2011 Acquisitions [Member] \| Preliminary Purchase Price Allocation [Member]
Equipment and leasehold improvements	213	213
Goodwill	20,367	21,500
Deferred tax asset (liability) associated with step-up in book basis	(356)	(356)
Assets acquired and liabilities assumed, net	2,823	2,598
Totals	45,144	46,052
Other 2011 Acquisitions [Member] \| Purchase Price Adjustments and Reclassifications [Member]
Goodwill	(1,133)
Assets acquired and liabilities assumed, net	225
Totals	(908)
Other 2011 Acquisitions [Member]
Totals		45,100
Preliminary Purchase Price Allocation [Member]
Equipment and leasehold improvements	$ 650	$ 650

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

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- Definition

The amount of acquisition cost of a business combination allocated to an identifiable intangible asset that will be amortized.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph e

-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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 52

-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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The total purchase price of the acquired entity. This includes cash paid to equity interest holders of the acquired entity, fair value of debt and equity securities issued to equity holders of the acquired entity, and transaction costs paid to third parties to consummate the acquisition.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph d

-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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 35

-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

Amount of acquisition cost of a business combination allocated to noncurrent deferred tax assets net of valuation allowance and noncurrent deferred tax liabilities.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph e

-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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 38

-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

Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 52

-Subparagraph c

-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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 53

-Subparagraph d

-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 amount of acquisition cost of a business combination allocated to property, plant and equipment to be used in ongoing operations.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph e

-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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 37

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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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