Derivative Financial Instruments	6 Months Ended
Sep. 30, 2013
Derivative Financial Instruments
Derivative Financial Instruments	Note 15—Derivative Financial Instruments As of September 30, 2013, we had recorded a derivative liability of $17.1 million representing the estimated fair value of our outstanding stock warrants which was triggered by our June 26, 2013 capital raise that included full ratchet anti-dilution protection for the new warrants issued during the offering. We valued these warrants by using the binomial lattice valuation model. With the anti-dilution protection afforded these new warrants, we no longer met the criteria for equity accounting for our warrants and therefore began accounting for all warrants as liabilities. In that our warrants were classified as equity at March 31, 2013, we had no similar liability at that date. See Note 13— Warrants. As of September 30, 2013, we also had an embedded derivative liability of $0.7 million relating to the embedded put option on the redeemable preferred stock held by Buffalo Management. This amount is included in other long-term liabilities on the balance sheet. The holder of this preferred stock may redeem their shares, in whole or in part, at any time following the three year anniversary of the date on which a minimum of 50,000 tonnes of potash has first shipped from our Holbrook Project. We estimated the value of the derivative liability by using scenario analysis based on various assumptions including: discount rate, preferred stock redemption periods, mine life and potash prices.

Note 15—Derivative Financial Instruments

As of September 30, 2013, we had recorded a derivative liability of $17.1 million representing the estimated fair value of our outstanding stock warrants which was triggered by our June 26, 2013 capital raise that included full ratchet anti-dilution protection for the new warrants issued during the offering. We valued these warrants by using the binomial lattice valuation model. With the anti-dilution protection afforded these new warrants, we no longer met the criteria for equity accounting for our warrants and therefore began accounting for all warrants as liabilities. In that our warrants were classified as equity at March 31, 2013, we had no similar liability at that date. See Note 13— Warrants.

As of September 30, 2013, we also had an embedded derivative liability of $0.7 million relating to the embedded put option on the redeemable preferred stock held by Buffalo Management. This amount is included in other long-term liabilities on the balance sheet. The holder of this preferred stock may redeem their shares, in whole or in part, at any time following the three year anniversary of the date on which a minimum of 50,000 tonnes of potash has first shipped from our Holbrook Project. We estimated the value of the derivative liability by using scenario analysis based on various assumptions including: discount rate, preferred stock redemption periods, mine life and potash prices.