Condensed Consolidated Balance Sheets (Unaudited) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
CURRENT ASSETS:
Cash and cash equivalents	$ 275,186	$ 240,031
Marketable securities	209,153	209,426
Accounts receivable, net of allowances of $2,880 and $3,094, respectively	113,057	96,982
Inventories	91,225	80,519
Deferred tax assets	9,801	12,252
Prepaid expenses and other current assets	37,622	40,269
Total current assets	736,044	679,479
Property and equipment, net	72,787	71,558
Investments	36,636	36,636
Deferred tax assets	12,291	11,510
Other assets	17,334	11,840
TOTAL ASSETS	875,092	811,023
CURRENT LIABILITIES:
Accounts payable	29,123	32,428
Accrued liabilities	28,920	40,369
Deferred revenue	81,826	60,327
Other current liabilities	8,462	11,249
Total current liabilities	148,331	144,373
Income taxes payable	17,502	17,323
Lease financing obligations, non-current	42,232	42,547
Deferred revenue, non-current	50,998	46,141
Other long-term liabilities	5,558	4,981
TOTAL LIABILITIES	264,621	255,365
Commitments and contingencies (Note 5)
STOCKHOLDERS’ EQUITY:
Preferred stock, $0.0001 par value—100,000 shares authorized, no shares issued and outstanding as of March 31, 2015 and December 31, 2014	0	0
Common stock, $0.0001 par value—1,000,000 shares authorized as of March 31, 2015 and December 31, 2014; 66,426 and 65,528 shares issued and outstanding as of March 31, 2015 and December 31, 2014, respectively	7	7
Additional paid-in capital	456,509	426,171
Retained earnings	154,306	129,814
Accumulated other comprehensive loss	(351)	(334)
TOTAL STOCKHOLDERS’ EQUITY	610,471	555,658
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY	$ 875,092	$ 811,023