Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash flows from operating activities:
Net income	$ 2,672	$ 7,602	$ 8,495
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	2,937	2,108	1,250
Deferred income tax benefit	(2,096)	(123)	(573)
Gain on sale of marketable securities			(278)
Loss on disposal of property and equipment	34	9	40
Stock-based compensation	1,980	1,937	1,542
Excess tax benefits from stock-based compensation	(13)	(58)	(64)
Changes in operating assets and liabilities:
Receivables	2,372	(302)	(2,572)
Inventories	(1,545)	(429)	1,486
Prepaid expenses and other current assets	(296)	(25)	930
Trade accounts payable	(1,414)	1,213	(194)
Income taxes payable / prepaid income taxes	(1,246)	276	623
Accrued compensation	114	44	1,948
Other accrued expenses and other current liabilities	(155)	(286)	(178)
Deferred income and customer deposits	3,720	(325)	1,707
Net cash provided by operating activities	7,064	11,641	14,162
Cash flows from investing activities:
Cash paid for acquisition of business, net of cash acquired	(39,379)
Purchase of cost method investment	(2,000)
Purchases of marketable securities			(70,479)
Maturities of marketable securities	8,585	28,555	106,231
Sales of marketable securities			6,835
Purchases of property and equipment	(1,177)	(4,178)	(424)
Issuance of note receivable	(500)	(290)
Net cash provided by (used in) investing activities	(34,471)	24,087	42,163
Cash flows from financing activities:
Repurchase of common stock	(6,028)	(1,826)
Payment of dividends	(4,595)
Contribution from noncontrolling interest		588
Principal payments on capital lease obligations	(20)	(19)	(35)
Excess tax benefits from stock-based compensation	13	58	64
Proceeds from employee stock plans	279	944	1,225
Net cash provided by (used in) financing activities	(10,351)	(255)	1,254
Effect of exchange rate changes on cash	(63)	2	43
Net increase (decrease) in cash and cash equivalents	(37,821)	35,475	57,622
Cash and cash equivalents, beginning of year	107,982	72,507	14,885
Cash and cash equivalents, end of year	70,161	107,982	72,507
Supplemental disclosures of net cash paid during the period for:
Income taxes	5,412	4,346	4,031
Non-cash investing and financing activities:
Stock issued for acquisition of business	9,544
Capital lease obligations			$ 98