Note 6 - Marketable Securities (Tables)

3 Months Ended

Mar. 31, 2021

Notes Tables

Marketable Securities [Table Text Block]

	As of March 31, 2021		As of December 31, 2020
Marketable securities:
Amortized cost	$	114,480	$	114,531
Unrealized gains, net		653,509		592,423
Total fair value	$	767,989	$	706,954