Stockholders' Equity (Schedule of Summary of Activity Under Stock Options Plans) (Details) shares in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) $ / shares shares
Stockholders' Equity [Abstract]
Shares, Outstanding, Beginning of Year | shares	734
Shares, Granted | shares	10
Shares, Exercised | shares	(2)
Shares, Forfeited | shares	(45)
Shares, Expired | shares	(30)
Shares, Outstanding, End of Year | shares	667
Shares, Exercisable, End of Year | shares	481
Shares, Vested and Expected to Vest, End of Year | shares	635
Weighted-Average Exercise Price, Outstanding, Beginning of Year | $ / shares	$ 9.06
Weighted-Average Exercise Price, Granted | $ / shares	4.70
Weighted-Average Exercise Price, Exercised | $ / shares	6.01
Weighted-Average Exercise Price, Forfeited | $ / shares	6.76
Weighted-Average Exercise Price, Expired | $ / shares	9.96
Weighted-Average Exercise Price, Outstanding, End of Year | $ / shares	9.12
Weighted-Average Exercise Price, Exercisable, End of Year | $ / shares	9.87
Weighted-Average Exercise Price, Vested and Expected to Vest, End of Year | $ / shares	$ 9.25
Weighted-Average Remaining Contractual Term, Outstanding, End of Year	6 years 8 months 16 days
Weighted-Average Remaining Contractual Term, Exercisable, End of Year	6 years 3 months 22 days
Weighted-Average Remaining Contractual Term, Vested and Expected to Vest, End of Year	2 months 12 days
Total Intrinsic Value, exercised | $
Aggregate Intrinsic Value, Outstanding, End of Year | $
Aggregate Intrinsic Value, Exercisable, End of Year | $
Aggregate Intrinsic Value, Vested and Expected to Vest, End of Year | $