Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 274,030	$ 230,263
Short-term investments	197,163	163,149
Accounts receivable, net	202,329	180,680
Inventories, net	173,052	172,109
Prepaid expenses and other current assets	70,075	49,001
Deferred income taxes, net	31,171	33,393
Total current assets	947,820	828,595
Property and equipment, net	264,086	260,568
Goodwill	144,325	146,520
Intangible assets, net	78,282	82,310
Other long-term assets	20,978	25,558
Total assets	1,455,491	1,343,551
Current liabilities:
Accounts payable	58,603	56,614
Accrued compensation	33,774	25,189
Deferred revenue - current	105,964	96,117
Accrued expenses and other liabilities	14,714	17,627
Other taxes payable	34,602	29,808
Total current liabilities	247,657	225,355
Deferred income taxes	47,406	44,620
Liability for uncertain tax positions	10,127	23,572
Deferred revenue- long term	26,452	21,389
Other long-term liabilities	6,353	5,531
Total liabilities	337,995	320,467
Commitments and contingencies
Stockholders' equity:
Preferred stock: par value $0.01; 5,000,000 shares authorized; none issued and outstanding
Common stock: par value $0.01; 360,000,000 shares authorized; 127,849,271 and 125,690,240 shares issued and outstanding, respectively	1,278	1,257
Additional paid-in capital	662,889	604,330
Retained earnings	464,993	414,947
Accumulated other comprehensive (loss) income	(11,664)	2,550
Total stockholders' equity	1,117,496	1,023,084
Total liabilities and stockholders' equity	$ 1,455,491	$ 1,343,551