Stock Plans (Restricted Shares Outstanding) (Details) - Restricted Stock [Member]	3 Months Ended
	Mar. 31, 2021 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Balance at beginning of period (in shares) | shares	304,000
Restricted stock vested (in shares) | shares	(41,000)
Restricted stock forfeited (in shares) | shares	(109,000)
Balance at end of period (in shares) | shares	154,000
Balance at beginning of period (in dollars per shares) | $ / shares	$ 6.78
Restricted stock vested (in dollars per shares) | $ / shares	8.23
Restricted stock forfeited (in dollars per shares) | $ / shares	8.23
Balance at end of period (in dollars per shares) | $ / shares	$ 5.38