Consolidated Statements Of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit	Total
Balances at Dec. 31, 2018	$ 11	$ 840,751	$ (270)	$ (880,515)	$ (40,023)
Balances (in shares) at Dec. 31, 2018	10,636
Vesting of restricted stock units (in shares)	1
Share-based compensation expense		468			468
Net unrealized (loss) gain on securities			249		249
Cumulative effect of accounting change				10	10
Net income (loss)				(7,949)	(7,949)
Balances at Mar. 31, 2019	$ 11	841,219	(21)	(888,454)	(47,245)
Balances (in shares) at Mar. 31, 2019	10,637
Balances at Dec. 31, 2019	$ 11	842,808	(35)	(912,008)	$ (69,224)
Balances (in shares) at Dec. 31, 2019	10,649				10,649
Share-based compensation expense		338			$ 338
Translation adjustment			143		143
Net income (loss)				(5,213)	(5,213)
Balances at Mar. 31, 2020	$ 11	$ 843,146	$ 108	$ (917,221)	$ (73,956)
Balances (in shares) at Mar. 31, 2020	10,649				10,649

Amount of increase to additional paid-in capital (APIC) for recognition of cost for award under share-based payment arrangement.

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