CONDENSED CONSOLIDATED STATEMENTS OF CASHFLOWS (USD $)	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Cash flows from operating activities:
Net loss	$ (106,743,000)	$ (133,655,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation, amortization and impairment charges	2,822,000	1,769,000
Stock-based compensation	16,945,000	19,928,000
Deferred executive compensation expense	119,000	683,000
Increase (decrease) from:
Accounts receivable	(3,665,000)	(4,888,000)
Inventory	(506,000)	(710,000)
Vendor advances	401,000	(3,636,000)
Other current assets	(2,633,000)	(3,057,000)
Other assets	1,876,000	(2,293,000)
Accounts payable	(1,173,000)	2,016,000
Accrued compensation and benefits	(90,000)	1,849,000
Accrued product development expenses	(2,527,000)	2,996,000
Other accrued expenses	(667,000)	3,481,000
Other liabilities	1,012,000	2,049,000
Deferred revenue	1,364,000	3,277,000
Deferred executive compensation paid	(2,630,000)	(3,953,000)
Net cash used in operating activities	(96,095,000)	(114,144,000)
Cash flows from investing activities:
Proceeds from maturities of marketable securities		25,000,000
Change in restricted cash		(6,133,000)
Investment in property and equipment	(2,010,000)	(1,749,000)
Net cash provided by (used in) investing activities	(2,010,000)	17,118,000
Cash flows from financing activities:
Proceeds from issuance of convertible debt	194,000,000
Proceeds from issuance of warrants	27,580,000
Purchase of convertible bond hedges	(43,220,000)
Repayment of long-term borrowings and capital lease obligation	(9,100,000)	(1,065,000)
Proceeds from issuance of common stock, net of issuance costs		310,037,000
Proceeds from issuance of common stock pursuant to stock option and purchase plans	2,262,000	2,344,000
Payment of tax withholding obligations related to stock compensation	(558,000)	(1,753,000)
Net cash provided by financing activities	170,964,000	309,563,000
Effect of exchange rates on cash	1,000	(25,000)
Net increase in cash and cash equivalents	72,860,000	212,512,000
Cash and cash equivalents, beginning of period	237,179,000	119,379,000
Cash and cash equivalents, end of period	310,039,000	331,891,000
Supplemental non-cash investing and financing disclosure:
Capitalization of construction-in-progress related to facility lease obligation	44,898,000	46,549,000
Investment in property and equipment included in accounts payable or accruals	121,000	1,478,000
Deferred financing costs included in accounts payable or accruals	$ 1,079,000