Condensed Consolidated Balance Sheets (USD $)	Mar. 31, 2014	Dec. 31, 2013
CURRENT ASSETS:
Cash and cash equivalents	$ 227,623,000	$ 226,022,000
Investment securities	76,224,000	70,869,000	[1]
Cash, cash equivalents and investment securities	303,847,000	296,891,000	[1]
Accounts receivable, net of allowance for doubtful accounts of $1,207 at March 31, 2014 and $1,208 at December 31, 2013	43,323,000	45,318,000	[1]
Inventories	36,687,000	34,451,000	[1]
Prepaid income taxes	4,440,000	5,966,000	[1]
Prepaid expenses and other current assets	8,065,000	7,319,000	[1]
Deferred income taxes	4,371,000	4,351,000	[1]
Total current assets	400,733,000	394,296,000	[1]
PROPERTY AND EQUIPMENT, net	90,379,000	87,861,000	[1]
GOODWILL	1,478,000	1,478,000	[1]
INTANGIBLE ASSETS, net	8,013,000	8,490,000	[1]
DEFERRED INCOME TAXES	5,829,000	7,518,000	[1]
TOTAL ASSETS	506,432,000	499,643,000	[1]
CURRENT LIABILITIES:
Accounts payable	11,714,000	11,335,000	[1]
Accrued liabilities	13,787,000	15,551,000	[1]
Total current liabilities	25,501,000	26,886,000	[1]
DEFERRED INCOME TAXES	4,011,000	3,630,000	[1]
INCOME TAX LIABILITY	2,713,000	4,402,000	[1]
COMMITMENTS AND CONTINGENCIES
STOCKHOLDERS' EQUITY:
Convertible preferred stock, $1.00 par value Authorized-500 shares; Issued and outstanding - none	0	0	[1]
Common stock, $0.10 par value - Authorized-80,000 shares; Issued 15,202 shares at March 31, 2014 and 15,103 at December 31, 2013, outstanding 15,175 shares at March 31, 2014 and 15,102 shares at December 31, 2013	1,520,000	1,510,000	[1]
Additional paid-in capital	83,043,000	78,495,000	[1]
Treasury stock, at cost - 27 shares at March 31, 2014 and 1 shares at December 31, 2013	(1,706,000)	(49,000)	[1]
Retained earnings	389,233,000	382,576,000	[1]
Accumulated other comprehensive loss	2,117,000	2,193,000	[1]
Total stockholders' equity	474,207,000	464,725,000	[1]
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	506,432,000	499,643,000	[1]
Allowance for doubtful accounts	1,207,000	1,208,000
Convertible preferred stock, par value	$ 1.00	$ 1.00
Convertible preferred stock, authorized shares	500,000	500,000
Convertible preferred stock, issued shares	$ 0	$ 0
Convertible preferred stock, outstanding shares	0	0
Common stock, par value	$ 0.10	$ 0.10
Common stock, shares authorized	80,000,000	80,000,000
Common stock, shares issued	15,202,000	15,103,000
Common Stock, Shares, Outstanding	15,175,000	15,102,000
Treasury Stock, shares	27,000	1,000

[1] December 31, 2013 balances were derived from audited consolidated financial statements.