Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Assets
Cash and cash equivalents	$ 58,780	$ 63,626
Short-term investments	169,167	120,664
Accounts receivable, net of allowance for doubtful accounts of $498 and $345 at December 31, 2011 and 2010, respectively	56,506	32,825
Inventories	41,285	37,088
Prepaid expenses and other current assets	6,848	7,777
Total current assets	332,586	261,980
Property, Plant, and Equipment, net	16,009	14,835
Other assets	4,853	4,479
Total assets	353,448	281,294
Liabilities and Stockholders' Equity
Notes payable	1,000	6,000
Accounts payable	10,980	13,154
Accrued expenses	22,373	12,028
Deferred product and services income	14,953	13,641
Total current liabilities	49,306	44,823
Other liabilities	8,113	5,344
Commitments and contingencies
Stockholders' equity:
Preferred Stock, $0.001 par value: 2,000,000 shares authorized; none issued	0	0
Common Stock, $0.001 par value: 40,000,000 shares authorized; 25,837,994 and 24,739,040 shares issued and outstanding at December 31, 2011 and 2010, respectively	27	27
Additional paid-in capital	278,204	252,565
Treasury stock: 1,837,801 and 1,838,801 shares at December 31, 2011 and 2010, respectively	(26,526)	(26,540)
Accumulated other comprehensive income, net	(99)	(118)
Retained Earnings	44,423	5,193
Total stockholders' equity	296,029	231,127
Total liabilities and stockholders' equity	$ 353,448	$ 281,294