CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Cash flows from operating activities:
Net income	$ 6,218	$ 11,185
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	3,434	3,966
Provision for doubtful accounts receivable, product returns, and inventory valuation	341	496
Stock compensation expense	1,708	1,872
Deferred taxes	1,151	2,475
Other	461	32
Changes in operating assets and liabilities, net of assets acquired and liabilities assumed in business combinations:
Change in operating assets	(1,542)	6,041
Change in operating liabilities	(32,354)	(6,611)
Net cash provided by (used in) operating activities	(20,583)	19,456
Cash flows from investing activities:
Purchases of property and equipment	(5,778)	(3,434)
Payments for intangible asset acquisitions	0	(7,000)
Net cash used in investing activities	(5,778)	(10,434)
Cash flows from financing activities:
Proceeds from exercise of stock options and issuance of common stock	2,227	2,697
Net cash provided by financing activities	2,227	2,697
Effect of exchange rate changes on cash and cash equivalents	285	(508)
Net decrease in cash and cash equivalents	(23,849)	11,211
Cash and cash equivalents, beginning of period	214,853	218,787
Cash and cash equivalents, end of period	$ 191,004	$ 229,998