Litigation, Other Contingencies and Guarantees (Narrative) (Details)
30 Months Ended
Apr. 30, 2016
USD ($)
Loss Contingencies [Line Items]  
Loss Contingency, Damages Awarded, Value $ 3,100,000
Estimate Potential Environmental Liabilities Minimum 19,000,000
Estimate Potential Environmental Liabilities Maximum 25,000,000
Recorded Best Estimate 23,000,000
ERISA Class Action Litigation [Member]  
Loss Contingencies [Line Items]  
Estimated Litigation Liability 5,000,000
Pricing Class Action Litigation [Member]  
Loss Contingencies [Line Items]  
Estimated Litigation Liability $ 50,000,000