Stock-based Compensation Expense (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Stock-based compensation expense:
Less stock-based compensation expense capitalized to inventory	$ (382)		$ (536)
Total stock-based compensation expense included in net loss	31,879	24,449	59,758	43,782
Stock options
Stock-based compensation expense:
Total stock-based compensation expense included in net loss	23,903	17,735	43,527	31,203
Type of award:
Unrecognized Expense, Net of Estimated Forfeitures	131,167		131,167
Weighted-average Recognition Period (in years)			2.65
Restricted stock and restricted stock units
Stock-based compensation expense:
Total stock-based compensation expense included in net loss	6,835	5,743	13,665	10,490
Type of award:
Unrecognized Expense, Net of Estimated Forfeitures	43,527		43,527
Weighted-average Recognition Period (in years)			2.36
ESPP share issuances
Stock-based compensation expense:
Total stock-based compensation expense included in net loss	1,523	971	3,102	2,089
Type of award:
Unrecognized Expense, Net of Estimated Forfeitures	2,522		2,522
Weighted-average Recognition Period (in years)			0.56
Research and development expenses
Stock-based compensation expense:
Total stock-based compensation expense included in net loss	20,453	17,735	39,002	32,055
Sales, general and administrative expenses
Stock-based compensation expense:
Total stock-based compensation expense included in net loss	$ 11,426	$ 6,714	$ 20,756	$ 11,727