Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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Note 2 - Summary of Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands		1 Months Ended	12 Months Ended
	Nov. 30, 2017	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2019	Jan. 01, 2018
Capitalized Computer Software, Net, Ending Balance		$ 4,900	$ 16,600	$ 4,900
Advertising Expense			11,800	10,700	$ 10,500
Research and Development Expense, Total			28,735	23,560	22,388
Payments to Acquire Businesses, Net of Cash Acquired, Total			90	$ 110,533
Cumulative Effect of New Accounting Principle in Period of Adoption			1,462
Accounting Standards Update 2016-02 [Member] \| Subsequent Event [Member]
Operating Lease, Right-of-Use Asset						$ 14,000
Operating Lease, Liability, Total						$ 14,000
Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption			$ 1,462
Retained Earnings [Member] \| Accounting Standards Update 2014-09 [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption							$ 1,500
Rapid [Member]
Business Combination, Consideration Transferred, Total	$ 121,900	121,959
Payments to Acquire Businesses, Net of Cash Acquired, Total	110,600	110,623
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable	$ 11,300	$ 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