Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred tax assets:
Net operating loss	$ 1,250,642	$ 996,172
Tax credit carryforwards	315,535	265,339
Intangible assets	14,673	3,174
Deferred revenues	9,341	15,771
Stock-based compensation	93,404	61,527
Inventories	5,913	13,395
Accrued expenses	27,236	37,699
Currency translation adjustment	222	0
Construction financing lease obligation	176,250	175,853
Gross deferred tax assets	1,893,216	1,568,930
Valuation allowance	(1,716,349)	(1,409,936)
Total deferred tax assets	176,867	158,994
Deferred tax liabilities:
Property and equipment	(175,424)	(158,994)
Acquired intangibles	(110,439)	(11,544)
Unrealized gain	(1,088)	0
Net deferred tax liabilities	$ (110,084)	$ (11,544)