Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 26, 2015
Current assets:
Cash and cash equivalents	$ 47,062	$ 38,154
Marketable securities	82,899	44,931
Accounts receivable, net of allowances of $73 and $150, respectively	39,457	37,832
Inventories	38,837	47,749
Inventories-delivered systems	2,457	2,856
Prepaid expenses and other	5,667	6,592
Total current assets	216,379	178,114
Property, plant and equipment, net	44,226	44,493
Goodwill	8,940	9,415
Intangible assets, net	412	1,867
Deferred income tax assets	17,399	1,118
Other assets	474	533
Total assets	287,830	235,540
Current liabilities:
Accounts payable	11,342	11,675
Accrued payroll and related expenses	12,656	10,097
Deferred revenue	9,168	12,790
Other current liabilities	8,047	8,878
Income taxes payable	813	1,771
Total current liabilities	42,026	45,211
Deferred revenue	816	827
Income taxes payable	841	775
Deferred tax liability	20	521
Other long-term liabilities	353	878
Total liabilities	44,056	48,212
Commitments and contingencies (Note 11)
Stockholders’ equity:
Preferred stock, $0.001 par value; 3,000,000 shares authorized; no shares issued or outstanding	0	0
Common stock, $0.001 par value, 47,000,000 shares authorized: 25,070,889 and 24,224,286, respectively, issued and outstanding	25	24
Additional paid-in capital	271,969	258,715
Accumulated deficit	(22,174)	(66,209)
Accumulated other comprehensive income	(6,046)	(5,202)
Total stockholders’ equity	243,774	187,328
Total liabilities and stockholders’ equity	$ 287,830	$ 235,540