Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred Tax Assets:
Goodwill, Noncurrent	$ 39,172	$ 13,716
Net operating loss carryforwards, Noncurrent	243,865	154,020
Tax credit carryforwards, Noncurrent	1,597	1,597
Start-up costs, Noncurrent	988	1,111
Stock-based compensation, Noncurrent	4,703	3,469
Terminal leases	3,859	4,229
Capitalized research and development, Noncurrent	8,096	3,711
Accrued compensation, Current	2,546	3,422
Inventory capitalization, Current	2,046	1,600
Allowance for doubtful accounts, Current	567	931
Other, Current		56
Other, Noncurrent	1,569	1,474
Deferred tax assets Current		6,009
Deferred tax assets Noncurrent	309,008	183,327
Deferred Tax Liabilities:
Prepaid expenses	(1,338)	(1,239)
Property, plant and equipment, Noncurrent	(65,398)	(53,133)
Intangibles, Noncurrent	(3,909)	(3,018)
Deferred revenue	0	(4,443)
Convertible debt	(3,626)	(4,599)
Unrealized gain (loss) on available for sale investments, current	(1,752)	(5,767)
Other, current		(527)
Other, Noncurrent	(2,007)	(1,867)
Deferred tax liabilities, Current		(16,575)
Deferred tax liabilities, Noncurrent	(78,030)	(58,018)
Net deferred tax (liabilities), Current		10,566
Net deferred tax assets, Noncurrent	230,978	125,309
Valuation Allowance, Current		(4,333)
Valuation Allowance, Noncurrent	(250,164)	(132,214)
Net deferred tax, Current		(14,899)
Net deferred tax, Noncurrent	$ (19,186)	$ (6,905)