23. Financial instruments
  | 
      
  | 
      Nominal value (in millions of euros)  | 
      
  | 
      Market value (in millions of euros)  | 
      
  | 
      Of which accounted for in equity  | 
      
  | 
      Maturity  | 
    ||||||||
  | 
      
  | 
      03/31/2016  | 
      
  | 
      03/31/2017  | 
      
  | 
      03/31/2016  | 
      
  | 
      03/31/2017  | 
      
  | 
      03/31/2016  | 
      
  | 
      03/31/2017  | 
      
  | 
      03/31/2016  | 
      
  | 
      03/31/2017  | 
    
  | 
      
  | 
      
  | 
      
  | 
      
  | 
      
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  | 
      
  | 
      
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  | 
      
  | 
      
  | 
      
  | 
      
  | 
      
  | 
      
  | 
      
  | 
    
Foreign currency hedges  | 
      
  | 
      826.4  | 
      
  | 
      1,533.4  | 
      
  | 
      2.3  | 
      
  | 
      –7.7  | 
      
  | 
      –2.7  | 
      
  | 
      –0.9  | 
      
  | 
      < 1 year  | 
      
  | 
      < 2 years  | 
    
thereof designated as hedge accounting  | 
      
  | 
      164.9  | 
      
  | 
      209.2  | 
      
  | 
      –2.7  | 
      
  | 
      –0.9  | 
      
  | 
      
  | 
      
  | 
      
  | 
      
  | 
      
  | 
      
  | 
      
  | 
    
Interest hedges  | 
      
  | 
      456.2  | 
      
  | 
      255.8  | 
      
  | 
      –7.0  | 
      
  | 
      –2.5  | 
      
  | 
      –4.5  | 
      
  | 
      –2.5  | 
      
  | 
      < 3 years  | 
      
  | 
      < 2 years  | 
    
thereof designated as hedge accounting  | 
      
  | 
      255.0  | 
      
  | 
      254.4  | 
      
  | 
      –4.5  | 
      
  | 
      –2.5  | 
      
  | 
      
  | 
      
  | 
      
  | 
      
  | 
      
  | 
      
  | 
      
  | 
    
Cross-Currency-Swaps  | 
      
  | 
      139.9  | 
      
  | 
      135.3  | 
      
  | 
      8.4  | 
      
  | 
      –13.3  | 
      
  | 
      
  | 
      
  | 
      
  | 
      
  | 
      ≤ 4 years  | 
      
  | 
      ≤ 3 years  | 
    
thereof designated as hedge accounting  | 
      
  | 
      0.0  | 
      
  | 
      0.0  | 
      
  | 
      0.0  | 
      
  | 
      0.0  | 
      
  | 
      
  | 
      
  | 
      
  | 
      
  | 
      
  | 
      
  | 
      
  | 
    
Commodity hedges  | 
      
  | 
      19.1  | 
      
  | 
      47.5  | 
      
  | 
      0.6  | 
      
  | 
      9.9  | 
      
  | 
      0.0  | 
      
  | 
      5.6  | 
      
  | 
      < 2 years  | 
      
  | 
      < 1 year  | 
    
thereof designated as hedge accounting  | 
      
  | 
      16.6  | 
      
  | 
      44.8  | 
      
  | 
      1.1  | 
      
  | 
      9.7  | 
      
  | 
      
  | 
      
  | 
      
  | 
      
  | 
      
  | 
      
  | 
      
  | 
    
Total  | 
      
  | 
      1,441.6  | 
      
  | 
      1,972.0  | 
      
  | 
      4.3  | 
      
  | 
      –13.6  | 
      
  | 
      –7.2  | 
      
  | 
      2.2  | 
      
  | 
      
  | 
      
  | 
      
  | 
    
thereof designated as hedge accounting  | 
      
  | 
      436.5  | 
      
  | 
      508.4  | 
      
  | 
      –6.1  | 
      
  | 
      6.3  | 
      
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