Stockholders' Equity And Stock-Based Compensation (Summary Of Stock Option Activity) (Details) - Stock Options [Member] - $ / shares shares in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Beginning Balance, Number of shares	1,229
Options granted, Number of shares	58
Options exercised, Number of shares	(4)
Options canceled, Number of shares
Options expired, Number of shares
Ending Balance, Number of shares	1,283	1,229
Exercisable, Number of shares	419
Beginning Balance, Weighted average exercise price per share	$ 3.82
Options granted, Weighted average exercise price per share	8.60
Options exercised, Weighted average exercise price per share	4.00
Options canceled, Weighted average exercise price per share
Options expired, Weighted average exercise price per share
Ending Balance, Weighted average exercise price per share	$ 4.03	$ 3.82
Weighted average remaining life	7 years 6 months	7 years 7 months 6 days