CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 174,674	$ 76,568
Short-term investments	103,604	32,874
Accounts receivable, net	63,889	65,238
Deferred income taxes	286	389
Prepaid expenses and other	5,245	5,178
Total current assets	347,698	180,247
Property and equipment, net	28,150	34,513
Deferred debt issuance costs, net	3,535	71
Deferred income taxes, net of current portion	1,921	2,321
Other assets, net	761	986
Goodwill	6,334	6,334
Total assets	388,399	224,472
Current liabilities:
Accounts payable	5,698	3,293
Accrued taxes	2,168	1,056
Accrued compensation and benefits	16,988	15,738
Accrued liabilities and other	12,932	10,403
Obligations under capital leases	333	326
Total current liabilities	38,119	30,816
Convertible notes, net	112,302	0
Obligations under capital leases, net of current portion	398	638
Other long-term liabilities	4,692	6,091
Total liabilities	155,511	37,545
Commitments and contingencies (Note 7)
Stockholders’ equity:
Common stock; $0.0001 par value; 1,000,000 shares authorized; 81,072 shares issued and 80,951 shares outstanding as of September 30, 2013; 75,758 shares issued and 75,637 shares outstanding as of December 31, 2012	8	8
Treasury stock	(441)	(441)
Additional paid-in capital	277,309	210,650
Accumulated deficit	(44,261)	(23,398)
Accumulated other comprehensive income	273	108
Total stockholders’ equity	232,888	186,927
Total liabilities and stockholders’ equity	$ 388,399	$ 224,472