Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating activities:
Net income	$ 29,463	$ 25,208	$ 10,964
Adjustments to reconcile net income to net cash provided by operating activities:
Non-cash expense related to stock-based compensation	4,441	3,465	4,007
Non-cash escrow share settlement			(1,866)
Provision for doubtful accounts	541		2,540
Provision for expiring inventory		2,099
Depreciation and amortization	931	852	860
Loss on maturity of available-for-sale investment			75
Loss on disposal of fixed assets	3	26	17
Deferred income taxes	12	(321)	191
Changes in operating assets and liabilities:
Accounts receivable, net	306	(3,276)	(3,999)
Inventories	1,432	5,382	(4,685)
Prepaid expenses and other assets	(1,020)	(277)	(202)
Restricted cash in escrow for SEC settlement (Notes 18 and 22)	(12,826)
Accounts payable	(2,295)	(5,485)	(134)
Accrued and other current liabilities	11,997	(414)	(1,006)
Deferred revenue	(422)	340	2,873
Other long-term liabilities	(56)	10	(133)
Net cash provided by operating activities	32,507	27,609	9,502
Investing activities:
Proceeds from the maturity of available-for-sale securities or short-term investments	75		379
Loans to third party (Note 6)	(7,250)	(4,751)
Purchases of property and equipment	(1,835)	(1,452)	(324)
Net cash (used in) provided by investing activities	(9,010)	(6,203)	55
Financing activities:
Repurchase of common stock including commissions	(12,811)	(24,400)	(12,519)
Repayment of credit facilities		(1,620)	(2,035)
Proceeds from borrowing on credit facilities			2,196
Decrease in restricted cash related to loan facility			2,300
Proceeds from issuances of common stock, net	4,392	5,214	1,705
Net cash used in financing activities	(8,419)	(20,806)	(8,353)
Effect of exchange rate changes on cash and cash equivalents	97	(175)	371
Net increase in cash and cash equivalents	15,175	425	1,575
Cash and cash equivalents, beginning of period	86,228	85,803	84,228
Cash and cash equivalents, end of period	101,403	86,228	85,803
Supplemental disclosure of cash flow information:
Net income taxes paid related to foreign operations	$ 1,509	944	2,237
Interest and unused line fees paid related to borrowings		$ 48	$ 81