Note 2 - Unaudited Pro Forma Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
As reported	$ 367,376	$ 288,360	$ 653,911	$ 600,178
Pro forma	367,376	369,815	683,258	744,326
As reported	20,888	14,844	31,096	34,529
Pro forma	$ 21,683	$ 18,454	$ 32,168	$ 35,847
As reported (in dollars per share)	$ 0.31	$ 0.21	$ 0.47	$ 0.49
Pro forma (in dollars per share)	$ 0.33	$ 0.26	$ 0.48	$ 0.51

The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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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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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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