Note 1 - Basis of Presentation (Details Textual) $ in Thousands	3 Months Ended
Mar. 31, 2017 USD ($)	Mar. 31, 2016 USD ($)
Number of Operating Segments	1
Income Tax Expense (Benefit)	$ 4,614	$ 5,633
Net Cash Provided by (Used in) Operating Activities, Continuing Operations	$ 6,705	$ (13,377)
Number of Reportable Segments	1
Accounting Standards Update 2016-09 [Member] \| New Accounting Pronouncement, Early Adoption, Effect [Member]
Income Tax Expense (Benefit)	$ 200
Net Cash Provided by (Used in) Operating Activities, Continuing Operations	$ 200
Domestic [Member]
Number of Offices	55
International [Member]
Number of Offices	10

Amount of cash inflow (outflow) from operating activities, excluding discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3521-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585

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