Segment Disclosures (Details 1) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Segment revenues:
Total revenues	$ 1,623	$ 1,752	$ 5,200	$ 5,617
Segment profit (loss)	412	446	1,355	1,504
Equity earnings (losses)	37	30	93	88
Income (loss) from investments	(1)		23	51
Operating income (loss)	336	373	1,112	1,232
Total assets and equity method investments by reporting segment
Total assets	26,455		26,455		24,327
Service [Member]
Segment revenues:
Total revenues	736	675	2,163	2,019
Product [Member]
Segment revenues:
Total revenues	887	1,077	3,037	3,598
Williams Partners [Member]
Total assets and equity method investments by reporting segment
Total assets	21,633		21,633		19,709
Williams Partners [Member] | Service [Member]
Segment revenues:
Total revenues	731	668	2,147	2,005
Williams Partners [Member] | Product [Member]
Segment revenues:
Total revenues	855	1,049	2,922	3,497
Williams NGL & Petchem Services [Member]
Total assets and equity method investments by reporting segment
Total assets	1,543		1,543		1,134
Williams NGL & Petchem Services [Member] | Service [Member]
Segment revenues:
Total revenues	0	2	3	2
Williams NGL & Petchem Services [Member] | Product [Member]
Segment revenues:
Total revenues	32	28	115	101
Access Midstream Partners G P L L C [Member]
Total assets and equity method investments by reporting segment
Total assets	2,162		2,162		2,187
Access Midstream Partners G P L L C [Member] | Service [Member]
Segment revenues:
Total revenues	0	0	0	0
Access Midstream Partners G P L L C [Member] | Product [Member]
Segment revenues:
Total revenues	0	0	0	0
Other [Member]
Total assets and equity method investments by reporting segment
Total assets	1,839		1,839		1,782
Other [Member] | Service [Member]
Segment revenues:
Total revenues	5	5	13	12
Other [Member] | Product [Member]
Segment revenues:
Total revenues	0	0	0	0
Operating Segments [Member]
Segment revenues:
Operating income (loss)	376	416	1,239	1,365
Operating Segments [Member] | Williams Partners [Member]
Segment revenues:
Total revenues	1,586	1,717	5,069	5,502
Segment profit (loss)	405	429	1,264	1,371
Equity earnings (losses)	31	30	84	87
Income (loss) from investments	0		0	0
Operating income (loss)	374	399	1,180	1,284
Operating Segments [Member] | Williams Partners [Member] | Service [Member]
Segment revenues:
Total revenues	731	668	2,147	2,005
Operating Segments [Member] | Williams Partners [Member] | Product [Member]
Segment revenues:
Total revenues	855	1,049	2,922	3,497
Operating Segments [Member] | Williams NGL & Petchem Services [Member]
Segment revenues:
Total revenues	59	62	221	201
Segment profit (loss)	(2)	16	56	72
Equity earnings (losses)	0	0	0	0
Income (loss) from investments	(1)		(3)	(2)
Operating income (loss)	(1)	16	59	74
Operating Segments [Member] | Williams NGL & Petchem Services [Member] | Service [Member]
Segment revenues:
Total revenues	0	2	3	2
Operating Segments [Member] | Williams NGL & Petchem Services [Member] | Product [Member]
Segment revenues:
Total revenues	59	60	218	199
Operating Segments [Member] | Access Midstream Partners G P L L C [Member]
Segment revenues:
Total revenues	0	0	0	0
Segment profit (loss)	6	0	35	0
Equity earnings (losses)	6	0	9	0
Income (loss) from investments	0		26	0
Operating income (loss)	0	0	0	0
Operating Segments [Member] | Access Midstream Partners G P L L C [Member] | Service [Member]
Segment revenues:
Total revenues	0	0	0	0
Operating Segments [Member] | Access Midstream Partners G P L L C [Member] | Product [Member]
Segment revenues:
Total revenues	0	0	0	0
Operating Segments [Member] | Other [Member]
Segment revenues:
Total revenues	7	7	21	20
Segment profit (loss)	3	1	0	61
Equity earnings (losses)	0	0	0	1
Income (loss) from investments	0		0	53
Operating income (loss)	3	1	0	7
Operating Segments [Member] | Other [Member] | Service [Member]
Segment revenues:
Total revenues	7	7	21	20
Operating Segments [Member] | Other [Member] | Product [Member]
Segment revenues:
Total revenues	0	0	0	0
Intersegment Elimination [Member]
Segment revenues:
Total revenues	(29)	(34)	(111)	(106)
Total assets and equity method investments by reporting segment
Total assets	(722)		(722)		(485)
Intersegment Elimination [Member] | Service [Member]
Segment revenues:
Total revenues	(2)	(2)	(8)	(8)
Intersegment Elimination [Member] | Product [Member]
Segment revenues:
Total revenues	(27)	(32)	(103)	(98)
Intersegment Elimination [Member] | Williams Partners [Member] | Service [Member]
Segment revenues:
Total revenues	0	0	0	0
Intersegment Elimination [Member] | Williams Partners [Member] | Product [Member]
Segment revenues:
Total revenues	0	0	0	0
Intersegment Elimination [Member] | Williams NGL & Petchem Services [Member] | Service [Member]
Segment revenues:
Total revenues	0	0	0	0
Intersegment Elimination [Member] | Williams NGL & Petchem Services [Member] | Product [Member]
Segment revenues:
Total revenues	(27)	(32)	(103)	(98)
Intersegment Elimination [Member] | Access Midstream Partners G P L L C [Member] | Service [Member]
Segment revenues:
Total revenues	0	0	0	0
Intersegment Elimination [Member] | Access Midstream Partners G P L L C [Member] | Product [Member]
Segment revenues:
Total revenues	0	0	0	0
Intersegment Elimination [Member] | Other [Member] | Service [Member]
Segment revenues:
Total revenues	(2)	(2)	(8)	(8)
Intersegment Elimination [Member] | Other [Member] | Product [Member]
Segment revenues:
Total revenues	0	0	0	0
General Corporate Expenses [Member]
Segment revenues:
Operating income (loss)	$ (40)	$ (43)	$ (127)	$ (133)