Note 15 - Stock-based Compensation (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Share-based Payment Arrangement, Option, Activity [Table Text Block]

				Weighted		Weighted
				Average		Average		Aggregate
	Number of			Exercise		Remaining		Intrinsic
	Options Shares			Price		Contract Life		Value
Outstanding Options, January 1, 2021		172,093,650		$	0.0611
Granted		22,228,550		$	0.1642
Exercised		(31,670,950	)	$	0.0513
Forfeited or expired		(7,253,450	)	$	0.1133
Outstanding Options, December 31, 2021		155,397,800		$	0.0755		3.61	$	4,678,202
Vested and Expected to Vest Options on December 31, 2021		144,959,889		$	0.0716		3.37	$	4,587,846
Exercisable Options on December 31, 2021		114,962,150		$	0.0588		2.47	$	4,198,094

Share-based Payment Arrangement, Option, Exercise Price Range [Table Text Block]

	Options Outstanding						Options Exercisable
			Weighted
			Average		Weighted				Weighted
			Remaining		Average		Number		Average
	Number		Contractual		Exercise		Exercisable		Exercise
Range of Exercise Prices	Outstanding		Life		Price		and Vested		Price
$0.0265 - $0.0314		39,467,850		2.85	$	0.0309		37,170,250	$	0.0309
$0.0318 - $0.0506		37,634,950		3.13	$	0.0410		31,750,250	$	0.0424
$0.0612 - $0.0800		35,893,450		0.87	$	0.0779		35,700,500	$	0.0780
$0.1270 - $0.1790		42,401,550		7.06	$	0.1454		10,341,150	$	0.1428
Balance, December 31, 2021		155,397,800		3.61	$	0.0755		114,962,150	$	0.0588

Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block]

	Stock Options									Employee Stock Purchase Plan
	Years Ended December 31									Years Ended December 31
	2021			2020			2019			2021			2020			2019
Risk-free interest rate		0.45%-0.92	%		0.21%-1.32	%		1.39%-2.43	%		0.04%-0.07	%		0.09%-1.57	%		1.52%-2.43	%
Expected life (in years)		5			5			5			0.25-0.26			0.25-0.26			0.25-0.26
Volatility		54%-56	%		42%-52	%		42	%		47%-97	%		37%-104	%		44%-58	%
Dividend		-			-			-			-			-			-

Schedule of Nonvested Restricted Stock Units Activity [Table Text Block]

				Weighted
	Number of			Average
	Outstanding			Grant-Date
	RSUs			Fair Value
Nonvested on January 1, 2021		92,341,800		$	0.0314
Granted		34,486,900		$	0.1287
Vested		(34,819,500	)	$	0.0335
Forfeited and expired		(2,682,500	)	$	0.0407
Nonvested on December 31, 2021		89,326,700		$	0.0679

Employee Stock Ownership Plan (ESOP) Disclosures [Table Text Block]

Outstanding stock options	155,397,800
Outstanding RSUs	89,326,700
Shares reserved for future Awards grants	96,195,700
Shares reserved for Employee Stock Purchase Plan	12,443,150
Total	353,363,350