Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Assets
Cash and cash equivalents	$ 39,844	$ 56,525
Trade accounts receivable, net	4,943	4,913
Inventory, net	14,256	16,251
Prepaid expenses and other current assets	2,632	2,210
Total current assets	61,675	79,899
Property and equipment, net	14,308	14,590
Other assets	6,297	6,151
Total assets	82,280	100,640
Liabilities and stockholders' equity
Accounts payable	4,245	5,168
Accrued expenses	13,018	11,093
Accrued compensation	3,089	3,805
Revolving credit facility	5,108	5,081
Long-term debt, current portion	11,140	9,758
Deferred revenue, current portion	0	8,462
Total current liabilities	36,600	43,367
Long-term debt, less current portion	39,157	42,070
Other long-term liabilities	6,245	5,891
Commitments and contingencies
Stockholders' equity:
Common stock	65	65
Additional paid-in capital	292,510	291,252
Accumulated deficit	(292,297)	(282,005)
Total stockholders' equity	278	9,312
Total liabilities and stockholders' equity	$ 82,280	$ 100,640