CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 66,836	$ 95,117
Short-term investments	27,672	27,669
Restricted cash	495	489
Accounts receivable, net	47,763	45,232
Inventories	44,341	46,901
Prepaid expenses and other current assets	14,307	20,173
Total current assets	201,414	235,581
Property, plant and equipment, net	59,942	66,765
Operating lease right-of-use assets	14,452	13,823
Purchased intangible assets, net	1,139	1,468
Goodwill	1,115	1,115
Other long-term assets	5,193	4,912
Total assets	283,255	323,664
Current liabilities:
Accounts payable	46,648	43,539
Current portion of long-term debt	3,033	3,232
Accrued and other current liabilities	25,461	42,053
Total current liabilities	75,142	88,824
Long-term debt, net of current portion	27,488	30,327
Operating lease liabilities, noncurrent	14,787	14,522
Other noncurrent liabilities	8,446	9,584
Total liabilities	125,863	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 June 30, 2021, 52,080 shares issued and outstanding; at December 31, 2020, 50,457 shares issued and outstanding	130	126
Additional paid-in capital	602,877	597,460
Accumulated other comprehensive income	1,423	1,735
Accumulated deficit	(447,038)	(418,914)
Total stockholders’ equity	157,392	180,407
Total liabilities and stockholders’ equity	$ 283,255	$ 323,664