CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 83,068	$ 95,117
Short-term investments	27,671	27,669
Restricted cash	488	489
Accounts Receivable, after Allowance for Credit Loss, Current	39,975	45,232
Inventories	46,373	46,901
Prepaid expenses and other current assets	15,425	20,173
Total current assets	213,000	235,581
Property, plant and equipment, net	60,977	66,765
Operating lease right-of-use assets	13,315	13,823
Purchased intangible assets, net	1,280	1,468
Goodwill	1,115	1,115
Other long-term assets	4,808	4,912
Total assets	294,495	323,664
Current liabilities:
Accounts payable	37,538	43,539
Current portion of long-term debt	3,026	3,232
Accrued and other current liabilities	32,672	42,053
Total current liabilities	73,236	88,824
Long-term debt, net of current portion	29,047	30,327
Operating lease liabilities, noncurrent	13,974	14,522
Other noncurrent liabilities	8,580	9,584
Total liabilities	124,837	143,257
Commitments and contingencies (Note 11)
Stockholders’ equity:
Preferred stock, $0.0025 par value, 10,000 shares authorized, no shares issued or outstanding	0	0
Common stock, $0.0025 par value, 100,000 shares authorized; at March 31, 2021, 51,009 shares issued and outstanding; at December 31, 2020, 50,457 shares issued and outstanding	128	126
Additional paid-in capital	599,744	597,460
Accumulated other comprehensive income (loss)	(608)	1,735
Accumulated deficit	(429,606)	(418,914)
Total stockholders’ equity	169,658	180,407
Total liabilities and stockholders’ equity	$ 294,495	$ 323,664