Note F - Stock-based Compensation (Tables)

12 Months Ended

Dec. 31, 2020

Notes Tables

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

	2020					2019					2018
	Shares			Weighted Average Fair Value at Grant Date		Shares			Weighted Average Fair Value at Grant Date		Shares			Weighted Average Fair Value at Grant Date
Non-vested at beginning of period		18,604		$	93.23		32,337		$	87.84		29,810		$	83.40
Granted		7,310			89.84		4,138			98.54		3,886			116.49
Vested		(3,193	)		59.94		(17,871	)		84.71		(1,359	)		72.25
Forfeited		0			-		0			-		0			-
Non-vested at end of period		22,721		$	96.82		18,604		$	93.23		32,337		$	87.84