Derivatives and Risk Management Activities (Details)	Sep. 30, 2013
Commodity Price Risk Hedging:
Derivative hedges to manage the risk of not utilizing storage capacity (in barrels per month)	2,200,000
Net long position associated with crude oil purchases
Commodity Price Risk Hedging:
Net derivative positions per day (in barrels)	316,500
Inventory hedged (in barrels, Mcf or megawatt hours)	9,800,000
Net short spread position hedging anticipated crude oil lease gathering purchases
Commodity Price Risk Hedging:
Net derivative positions per day (in barrels)	32,800
Inventory hedged (in barrels, Mcf or megawatt hours)	13,000,000
Crude oil grade spread positions related to anticipated purchases and sales of crude oil
Commodity Price Risk Hedging:
Net derivative positions per day (in barrels)	13,700
Inventory hedged (in barrels, Mcf or megawatt hours)	1,700,000
Butane/WTI spread positions
Commodity Price Risk Hedging:
Net derivative positions per day (in barrels)	2,500
Inventory hedged (in barrels, Mcf or megawatt hours)	1,400,000
Long natural gas position for anticipated base gas requirements
Commodity Price Risk Hedging:
Inventory hedged (in barrels, Mcf or megawatt hours)	1,300,000
Short position related to anticipated sales of crude oil, NGL and refined products inventory
Commodity Price Risk Hedging:
Inventory hedged (in barrels, Mcf or megawatt hours)	10,700,000
Short natural gas position related to anticipated natural gas sales
Commodity Price Risk Hedging:
Inventory hedged (in barrels, Mcf or megawatt hours)	29,400,000
PLA crude oil net short position
Commodity Price Risk Hedging:
Net derivative positions per day (in barrels)	1,700
Inventory hedged (in barrels, Mcf or megawatt hours)	1,400,000
PLA Crude oil long call option position
Commodity Price Risk Hedging:
Inventory hedged (in barrels, Mcf or megawatt hours)	600,000
Long natural gas position for natural gas purchases
Commodity Price Risk Hedging:
Inventory hedged (in barrels, Mcf or megawatt hours)	16,300,000
Short propane position related to subsequent sale of products
Commodity Price Risk Hedging:
Inventory hedged (in barrels, Mcf or megawatt hours)	2,900,000
Short Butane position related to subsequent sale of products
Commodity Price Risk Hedging:
Inventory hedged (in barrels, Mcf or megawatt hours)	900,000
Short WTI position related to subsequent sale of products
Commodity Price Risk Hedging:
Inventory hedged (in barrels, Mcf or megawatt hours)	300,000
Long power position for power supply requirements
Commodity Price Risk Hedging:
Inventory hedged (in barrels, Mcf or megawatt hours)	500,000