Income Taxes (Details 2)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Schedule of reconciliation of the federal statutory rate to the Company's effective tax rate
Federal income tax provision at statutory rate	35.00%	35.00%	35.00%
State income taxes, net of federal income tax benefit	1.30%	0.70%	1.40%
Foreign income tax rate differential	(3.90%)	(6.80%)	(4.90%)
Change in statutory tax rates	(0.80%)	0.90%	1.50%
Tax credits	(0.50%)	(2.00%)	(7.80%)
Change in unrecognized tax benefits, net	0.40%	(11.60%)	(12.40%)
Cellulosic biofuel credit, net of incremental state tax and manufacturing deduction benefit	(6.10%)		(69.30%)
Adjustment for prior year estimates			(6.80%)
Valuation allowance		3.20%
Other	(0.60%)	(3.40%)	1.00%
Provision/(benefit) for income taxes	24.80%	16.00%	(62.30%)

Effective income tax rate reconciliation adjustment for prior year estimates.

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Effective income tax rate reconciliation change in unrecognized tax benefits net.

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Effective income tax rate reconciliation tax credits net of incremental state tax and manufacturing deduction benefit.

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A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

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-Topic 235

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- Definition

The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to changes in the valuation allowance for deferred tax assets.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit that is attributable to changes in the income tax laws or rates.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by the difference between statutory income tax rates in foreign jurisdictions and the domestic federal statutory income tax rate recorded during the period.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to all other items not otherwise listed in the existing taxonomy.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by the state and local income tax expense or benefit, net of the federal tax benefit (expense) thereon, recorded during the period.

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The sum of the differences between the effective income tax rate and domestic federal statutory income tax rate that can be explained by all tax credits generated or utilized under enacted tax laws during the period.

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