CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
CURRENT ASSETS:
Cash and cash equivalents	$ 80,162	$ 134,137
Short-term marketable securities	164,649	94,451
Accounts receivable, net of allowances for doubtful accounts of $763 and $706 in 2019 and 2018, respectively	25,819	11,072
Inventories	88,710	80,857
Prepaid expenses and other current assets	15,316	11,915
Total current assets	374,656	332,432
PROPERTY AND EQUIPMENT, net	114,930	114,117
INTANGIBLE ASSETS, net	18,238	21,152
GOODWILL	91,849	91,849
DEFERRED TAX ASSETS	5,564	6,906
OTHER ASSETS	31,173	22,241
Total assets	636,410	588,697
CURRENT LIABILITIES:
Accounts payable	30,542	31,552
Accrued payroll and related expenses	10,796	12,131
Taxes payable	597	933
Other accrued liabilities	7,717	3,750
Total current liabilities	49,652	48,366
LONG-TERM INCOME TAXES PAYABLE	9,309	8,652
DEFERRED TAX LIABILITIES	152	216
OTHER LIABILITIES	11,969	4,391
Total liabilities	71,082	61,625
COMMITMENTS AND CONTINGENCIES (Notes 11, 12, 13 and 14)
STOCKHOLDERS’ EQUITY:
Common stock	28	28
Additional paid-in capital	143,554	126,164
Accumulated other comprehensive loss	(1,084)	(1,689)
Retained earnings	422,830	402,569
Total stockholders’ equity	565,328	527,072
Total liabilities and stockholders’ equity	$ 636,410	$ 588,697