Basis of Presentation and Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2013

Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block]

Accounts receivable as of December 31, 2013 and 2012 are detailed below.



	December 31,
	2013			2012
	($ in millions)
Natural gas, oil and NGL sales	$	1,548		$	1,457
Joint interest	417			592
Oilfield services	63			24
Related parties^(a)	62			23
Other	150			168
Allowance for doubtful accounts	(18		)	(19		)
Total accounts receivable, net	$	2,222		$	2,245

___________________________________________


(a)	See Note 7 for discussion of related party transactions.

Capitalized Costs Relating to Oil and Gas Producing Activities [Table Text Block]

The table below sets forth the cost of unproved properties excluded from the amortization base as of December 31, 2013 and the year in which the associated costs were incurred.



	Year of Acquisition
	2013		2012		2011		Prior		Total
	($ in millions)
Leasehold acquisition cost	$	229	$	1,648	$	2,113	$	5,066	$	9,056
Exploration cost	623		341		93		8		1,065
Capitalized interest	667		516		270		439		1,892
Total	$	1,519	$	2,505	$	2,476	$	5,513	$	12,013