Note 10 - Acquisitions (Details) - Business Acquisition, Unaudited Pro Forma Summary (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Business Acquisition, Unaudited Pro Forma Summary [Abstract]
Revenue	$ 1,297,479	$ 1,162,850	$ 3,652,673	$ 3,280,183
Income from continuing operations, net of tax	$ 34,542	$ 31,959	$ 95,141	$ 81,387
Basic income per share from continuing operations, net of tax	$ 1.32	$ 1.24	$ 3.65	$ 3.16
Diluted income per share from continuing operations, net of tax	$ 1.31	$ 1.22	$ 3.61	$ 3.11

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The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect per basic share of common stock for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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- Definition

The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, per diluted share of common stock for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

+ Details

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The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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