Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Stockholders' Equity Attributable to Parent	$ (270,678)	$ (267,328)	$ (279,003)	$ (270,489)
Accumulated Translation Adjustment [Member]
Stockholders' Equity Attributable to Parent	2,623	2,685	1,645
Net current period other comprehensive gain (loss)	(62)	1,040
Reclassification of accumulated other comprehensive income (loss)	0	0
Accumulated Net Unrealized Investment Gain (Loss) [Member]
Stockholders' Equity Attributable to Parent	0	(33)	150
Net current period other comprehensive gain (loss)	33	(183)
Reclassification of accumulated other comprehensive income (loss)	0	0
Accumulated Other Comprehensive Income (Loss) [Member]
Stockholders' Equity Attributable to Parent	2,623	2,652	$ 1,795	$ 1,085
Net current period other comprehensive gain (loss)	(29)	857
Reclassification of accumulated other comprehensive income (loss)	$ 0	$ 0