XML 151 R105.htm IDEA: XBRL DOCUMENT v3.8.0.1
Acquisitions - National Cooperative Refinery Association Acquisition (Details)
$ in Millions
12 Months Ended 37 Months Ended
Oct. 01, 2016
USD ($)
Aug. 31, 2017
USD ($)
Aug. 31, 2015
USD ($)
Sep. 30, 2015
USD ($)
Sep. 01, 2015
Nov. 29, 2011
contingent_payments
National Cooperative Refinery Association            
Business Acquisition [Line Items]            
Business Combination, Step Acquisition, Equity Interest in Acquiree, Percentage         100.00% 74.40%
Business Combination, Consideration Transferred       $ 351.0    
Number of purchase price payments | contingent_payments           2
National Cooperative Refinery Association | Interest, Net            
Business Acquisition [Line Items]            
Patronage earned by member   $ 0.0 $ 31.0      
Crack Spread Contingent Payment [Member]            
Business Acquisition [Line Items]            
Business Acquisition, Contingent Consideration, Potential Cash Payment $ 19.1 $ 0.0