Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Cash flows from operating activities:
Net income (loss)	$ (917)	$ 4,898
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Provision for doubtful accounts	244	726
Depreciation and amortization	6,674	4,301
Deferred income taxes	(1,249)	923
Loss (gain) on derivative instruments	(82)	(73)
Compensation expense related to stock-based awards and employee stock purchase plan	2,827	2,988
Changes in operating assets and liabilities:
Accounts receivable	481	3,573
Inventories	(2,327)	(1,831)
Prepaid expenses and other assets	(528)	(84)
Other non-current assets	496	(387)
Accounts payable	3,315	278
Deferred revenue	1,285	796
Accrued expenses	610	(117)
Other long-term liabilities	(170)	982
Net cash provided by operating activities	10,659	16,973
Cash flows from investing activities:
Capital expenditures	(3,535)	(3,031)
Net cash paid for business acquired	45,165	22,943
Purchases of marketable securities	(10,618)	(35,221)
Maturities and sales of marketable securities	32,529	16,166
Net cash used in investing activities	(26,789)	(45,029)
Cash flows from financing activities:
Repayments of long-term debt	(951)	(772)
Proceeds from long-term debt	0	4,671
Repayments of Long-term loan	1,219	0
Proceeds from Long-term loan	65,000	0
Repayments of Long-term Lines of Credit	30,000	0
Proceeds from Long-term Lines of Credit	0	23,000
Payments of employee restricted stock withholdings	482	828
Proceeds From Stock Options Exercised and Employee Stock Purchase Plan	572	2,360
Payment of Stock Registration Fee	0	5
Net cash provided by financing activities	32,920	28,426
Effect of exchange rate changes on cash and cash equivalents	(225)	(135)
Net increase in cash and cash equivalents	16,565	235
Cash and cash equivalents at beginning of period	9,358	8,978
Cash and cash equivalents at end of period	$ 25,923	$ 9,213