CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOW - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Cash flows from operating activities:
Net loss	$ (12,708)	$ (15,466)
Adjustments to reconcile net loss to net cash used for operating activities from continuing operations:
Depreciation and amortization	291	385
Amortization of debt issuance costs and discounts	4,535	4,180
Amortization of discount or premium on available-for-sale securities	253	838
Share-based compensation expense	252	1,550
Changes in assets and liabilities:
Accounts receivable	(2,858)	(117)
Inventories	2,178	(1,483)
Prepaid expenses and other assets	4,104	848
Accounts payable	604	(1,073)
Accrued and other liabilities	(5,644)	(31)
Deferred revenue	(2,745)	(1,053)
Net cash used for operating activities	(11,738)	(11,422)
Cash flows from investing activities:
Property and equipment purchases		(47)
Purchases of available-for-sale securities	(30,423)	(47,488)
Proceeds from maturity of available-for-sale securities	29,000	74,750
Proceeds from Sale of Available-for-sale Securities	3,666
Net cash provided by (used for) investing activities	2,243	27,215
Cash flows from financing activities:
Payments of note payable	(2,199)	(79)
Net cash used for financing activities	(2,199)	(79)
Net decrease in cash and cash equivalents	(11,694)	15,714
Cash and cash equivalents:
Beginning of period	95,395	83,174
End of period	$ 83,701	$ 98,888