Note 3 - Summary of Accounting Policies (Details Textual) - USD ($) xbrli-pure in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2021	Dec. 31, 2018
Stockholders' Equity Attributable to Parent, Ending Balance	$ 27,167,932	$ 13,156,005		$ 8,805,010
Property, Plant and Equipment, Gross, Ending Balance	185,600	185,500
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Ending Balance	165,000	151,200
Depreciation, Total	19,000	22,000
Impairment of Intangible Assets, Finite-lived	0	0
Intangible Assets, Net (Excluding Goodwill), Total	53,500	173,500
Finite-Lived Intangible Assets, Accumulated Amortization	40,100	105,000
Amortization of Intangible Assets, Total	$ 27,600	$ 30,800
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	0.00%
Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	3 years
Finite-Lived Intangible Asset, Useful Life (Year)	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Vesting Term (Year)	1 year
Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	5 years
Finite-Lived Intangible Asset, Useful Life (Year)	10 years
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Vesting Term (Year)	4 years
Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2020-06 [Member] | Subsequent Event [Member]
Stockholders' Equity Attributable to Parent, Ending Balance			$ 13,003,075