Income Taxes	3 Months Ended
Mar. 31, 2015
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Our income tax provision for the three months ended March 31, 2015 was $112.7 million on pre-tax income of $333.7 million, or an effective tax rate of 33.8%, compared to an income tax provision of $413.2 million on pre-tax income of $1,130.1 million, or an effective tax rate of 36.6%, for the three months ended March 31, 2014. Our effective tax rate was lower in the three months ended March 31, 2015 principally due to the higher effective tax rate on the gain related to the sale of our phosphate mining and manufacturing business in March 2014. Our effective tax rate based on pre-tax earnings differs from our effective tax rate based on pre-tax earnings exclusive of the noncontrolling interest, as our consolidated income tax provision does not include a tax provision on the earnings attributable to the noncontrolling interest in Terra Nitrogen Company, L.P. (TNCLP), which does not record an income tax provision. Our unrecognized tax benefits are $135.8 million as of March 31, 2015 of which approximately $97.0 million would impact our effective tax rate if these unrecognized tax benefits were to be recognized in the future.

Income Taxes

3 Months Ended

Mar. 31, 2015

Our income tax provision for the three months ended March 31, 2015 was $112.7 million on pre-tax income of $333.7 million, or an effective tax rate of 33.8%, compared to an income tax provision of $413.2 million on pre-tax income of $1,130.1 million, or an effective tax rate of 36.6%, for the three months ended March 31, 2014. Our effective tax rate was lower in the three months ended March 31, 2015 principally due to the higher effective tax rate on the gain related to the sale of our phosphate mining and manufacturing business in March 2014.

Our effective tax rate based on pre-tax earnings differs from our effective tax rate based on pre-tax earnings exclusive of the noncontrolling interest, as our consolidated income tax provision does not include a tax provision on the earnings attributable to the noncontrolling interest in Terra Nitrogen Company, L.P. (TNCLP), which does not record an income tax provision.

Our unrecognized tax benefits are $135.8 million as of March 31, 2015 of which approximately $97.0 million would impact our effective tax rate if these unrecognized tax benefits were to be recognized in the future.