Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 26, 2015	Dec. 27, 2014
Current assets:
Cash and cash equivalents	$ 41,561	$ 34,676
Marketable securities	43,065	49,286
Accounts receivable, net of allowances of $159 and $253, respectively	37,573	26,121
Inventories	48,398	35,105
Inventories-delivered systems	1,543	1,912
Prepaid expenses and other	6,651	9,289
Deferred income tax assets	1,438	1,457
Total current assets	180,229	157,846
Property, plant and equipment, net	45,944	49,633
Goodwill	9,678	10,494
Intangible assets, net	2,403	4,294
Deferred income tax assets	385	410
Other assets	497	559
Total assets	239,136	223,236
Current liabilities:
Accounts payable	15,882	10,199
Accrued payroll and related expenses	10,025	8,700
Deferred revenue	10,985	10,021
Other current liabilities	9,422	8,265
Income taxes payable	1,236	1,017
Total current liabilities	47,550	38,202
Deferred revenue	939	2,591
Income taxes payable	776	701
Deferred tax liabilities	1,054	926
Other long-term liabilities	1,018	1,279
Total liabilities	$ 51,337	$ 43,699
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: 24,176,806 and 23,813,729, respectively, issued and outstanding	24	24
Additional paid-in capital	256,878	251,396
Accumulated deficit	(64,396)	(69,114)
Accumulated other comprehensive income (loss)	(4,707)	(2,769)
Total stockholders’ equity	187,799	179,537
Total liabilities and stockholders’ equity	$ 239,136	$ 223,236