Income Taxes (Schedule of Deferred Tax Assets and Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Deferred tax assets:
Accrued bonuses	$ 315	$ 0
Accrued severance pay	11	0
Stock-based compensation	14	0
Federal net operating loss carryover	62,575	0
State net operating loss carryover	1,161	0
Basis in partnerships	26,123	0
Warranty accrual	161	0
Historical BioFuel capitalized start-up costs	24	0
Historical BioFuel - other	16us-gaap_DeferredTaxAssetsOther	0us-gaap_DeferredTaxAssetsOther
Deferred tax assets, gross	90,400us-gaap_DeferredTaxAssetsGross	0us-gaap_DeferredTaxAssetsGross
Valuation allowance	(1,161)	0	0
Deferred tax assets, net	89,239us-gaap_DeferredTaxAssetsNet	0us-gaap_DeferredTaxAssetsNet
Deferred tax liabilities:
Prepaid insurance	(11)	0
Noncontrolling interests impact of M-1s	(31)	0
Deferred tax liabilities, net	$ (42)us-gaap_DeferredTaxLiabilities	$ 0us-gaap_DeferredTaxLiabilities

Deferred Tax Assets, Basis in Partnership

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The deferred tax assets that are capitalized of which start-up costs are reported in the period.

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Deferred Tax Liabilities, Impact of Noncontrolling Interests

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible domestic operating loss carryforwards. Excludes state and local operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from employee bonuses.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from severance costs.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from warranty reserves.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of deferred tax liability attributable to taxable temporary differences net of deferred tax asset attributable to deductible temporary differences and carryforwards after valuation allowances.

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Amount of deferred tax consequences attributable to taxable temporary differences derived from prepaid expenses.

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