OTHER LIABILITIES, INCLUDING EMPLOYEE BENEFITS (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Employee Benefits [Line Items]
Defined Benefit Plan, Vesting Period	5 years
Pension, postretirement, postemployment and other employment benefits	$ 1,430	[1]	$ 1,225	[1]
Commodity derivative contracts	99		320
Reserve for uncertain tax benefits	68		87
Other	363		263
Total other liabilities	1,861		1,690
Number of years Mercer Pension Discount Curve consists of spot interest rates at half-year increments	30 years
Years of service required for annuity to equal percentage of executive's highest average compensation for any consecutive three-year period during the preceeding five years before retirement	25 years
Estimated future average expected rate of return per annum on pension assets	7.25%
Estimated future average expected rate of return on passively managed pension assets	6.75%
Estimated future average expected premium on actively managed pension assets	0.50%
Accumulated benefit obligations in excess of plan assets [Abstract]
Projected benefit obligation	2,221		2,180
Accumulated benefit obligation	2,090		1,933
Fair value of plan assets	1,433		1,490
Balance of unfunded defined contribution plan	69		65
Costs charged to operations for employee savings plans and defined contribution plans	79		66		43
Costs capitalized to oil and gas properties for employee savings plans and defined benefit contribution plans	11		5
Other Liabilities [Member]
Employee Benefits [Line Items]
Commodity derivative contracts	$ 0		$ 115

[1] Refer to Note 7 for current portion.