Description of Business and Summary of Significant Accounting Policies (Computation of basic and diluted net income (loss) per share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Schedule of computation of basic and diluted net income (loss) per share
Loss from continuing operations, net of income taxes	$ (44,442)	$ (53,862)
Income from discontinued operations, net of income taxes	7,894	10,733
Net loss	$ (36,548)	$ (43,129)
Weighted average common shares outstanding, basic and diluted	41,031	35,480
Net income (loss) per share - basic and diluted:
Net loss per share - continuing operations	$ (1.08)	$ (1.52)
Net income per share - discontinued operations	0.19	0.30
Net loss per share - basic and diluted	$ (0.89)	$ (1.22)