Financial Instruments (Unaudited) (Details) - Commodity Contract [Member] - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Fair Value Hedging [Member] | Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative financial instruments		$ (4)	$ 12	$ 2	$ 0
Hedged item – firm sales commitments		4	(12)	(2)	0
Matured derivative financial instruments		(1)	(2)	(11)	(4)
Derivatives not designated as hedging instruments [Member] | Embedded derivatives in provisional sales contracts [Member] | Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Realized and unrealized gains (losses)	[1]	(78)	84	(150)	(85)
Derivatives not designated as hedging instruments [Member] | Copper forward contracts [Member] | Amounts recorded in Cost of Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Realized and unrealized gains (losses)	[2]	(6)	4	(7)	5
Derivatives not designated as hedging instruments [Member] | Plains Exploration & Production Company [Member] | Crude Oil Options [Member] | Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Realized and unrealized gains (losses)	[1]	6	(68)	58	(104)
Derivatives not designated as hedging instruments [Member] | Plains Exploration & Production Company [Member] | Natural gas swaps [Member] | Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Realized and unrealized gains (losses)	[1]	$ 0	$ (2)	$ 0	$ (16)

[1] Amounts recorded in revenues.

[2] Amounts recorded in cost of sales as production and delivery costs.