XML 80 R66.htm IDEA: XBRL DOCUMENT v3.7.0.1
Derivative Instruments, Hedging Activities and Fair Value Measurements, Level 3 Recurring Valuation Techniques (Details)
$ in Millions
3 Months Ended
Mar. 31, 2017
USD ($)
$ / bbl
Dec. 31, 2016
USD ($)
Asset commodity derivatives - Crude oil [Member] | Liability commodity derivatives - Crude oil [Member] | Level 3 [Member]    
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]    
Fair Value Measurements, Valuation Techniques Discounted cash flow  
Input description Forward commodity prices  
Asset commodity derivatives - Crude oil [Member] | Liability commodity derivatives - Crude oil [Member] | Level 3 [Member] | Minimum [Member]    
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]    
Fair value inputs, forward commodity price (in dollars per unit) | $ / bbl 48.68  
Asset commodity derivatives - Crude oil [Member] | Liability commodity derivatives - Crude oil [Member] | Level 3 [Member] | Maximum [Member]    
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]    
Fair value inputs, forward commodity price (in dollars per unit) | $ / bbl 51.93  
Fair Value, Measurements, Recurring [Member]    
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]    
Commodity asset derivatives $ 41.2 $ 541.4
Commodity liability derivatives 44.5 739.4
Fair Value, Measurements, Recurring [Member] | Level 3 [Member]    
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]    
Commodity asset derivatives 1.5 1.7
Commodity liability derivatives 0.8 $ 0.3
Fair Value, Measurements, Recurring [Member] | Liability commodity derivatives - Crude oil [Member] | Level 3 [Member]    
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]    
Commodity liability derivatives 0.8  
Fair Value, Measurements, Recurring [Member] | Asset commodity derivatives - Crude oil [Member] | Level 3 [Member]    
Fair Value Measurements, Recurring, Valuation Techniques [Line Items]    
Commodity asset derivatives $ 1.5