Common Stock and Senior Convertible Preferred Stock (Tables)

12 Months Ended

Dec. 31, 2020

Equity [Abstract]

Schedule of Changes in Senior Convertible Preferred Stock, Common Stock and Treasury Stock

Changes in senior convertible preferred stock, common stock and treasury stock for the three years ended December 31, 2020 are as follows:

	December 31,
	2020			2019			2018
(Shares in thousands)
Senior Convertible Preferred Stock:
Balance at beginning and end of year		0			0			0
Common Stock:
Balance at beginning of year		23,321			23,029			22,384
Issued for employee stock plans		367			292			645
Balance at end of year		23,688			23,321			23,029
Treasury Stock:
Balance at beginning of year		(2,516	)		(2,480	)		(1,606	)
Shares repurchased		(74	)		(36	)		(874	)
Balance at end of year		(2,590	)		(2,516	)		(2,480	)