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Note 2 - Summary of Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands		12 Months Ended
	Nov. 30, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2019	Jan. 01, 2018
Capitalized Computer Software, Net, Ending Balance		$ 32,700	$ 16,600
Advertising Expense		13,000	11,800	$ 10,700
Research and Development Expense, Total		32,692	28,735	23,560
Payments to Acquire Businesses, Net of Cash Acquired, Total		(0)	90	$ 110,533
Operating Lease, Right-of-Use Asset		11,425	0
Cumulative Effect of New Accounting Principle in Period of Adoption			1,462
Operating Lease, Liability, Total		$ 11,905
Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption			$ 1,462
Accounting Standards Update 2016-02 [Member]
Operating Lease, Right-of-Use Asset					$ 13,100
Operating Lease, Liability, Total					$ 13,100
Accounting Standards Update 2014-09 [Member] \| Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption						$ 1,500
Rapid [Member]
Business Combination, Consideration Transferred, Total	$ 121,959
Payments to Acquire Businesses, Net of Cash Acquired, Total	110,623
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable	$ 11,336
Building [Member]
Property, Plant and Equipment, Useful Life		39 years
Minimum [Member]
Property, Plant and Equipment, Useful Life		3 years
Finite-Lived Intangible Asset, Useful Life		2 years
Minimum [Member] \| Equipment [Member]
Property, Plant and Equipment, Useful Life		3 years
Minimum [Member] \| Office Furniture And Equipment [Member]
Property, Plant and Equipment, Useful Life		3 years
Minimum [Member] \| Computer Equipment [Member]
Property, Plant and Equipment, Useful Life		3 years
Minimum [Member] \| Land, Buildings and Improvements [Member]
Property, Plant and Equipment, Useful Life		10 years
Maximum [Member]
Property, Plant and Equipment, Useful Life		39 years
Finite-Lived Intangible Asset, Useful Life		10 years
Maximum [Member] \| Equipment [Member]
Property, Plant and Equipment, Useful Life		15 years
Maximum [Member] \| Office Furniture And Equipment [Member]
Property, Plant and Equipment, Useful Life		7 years
Maximum [Member] \| Computer Equipment [Member]
Property, Plant and Equipment, Useful Life		5 years
Maximum [Member] \| Land, Buildings and Improvements [Member]
Property, Plant and Equipment, Useful Life		39 years