Consolidated Statement of Income (Unaudited) - USD ($) shares in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenues:
Revenues	$ 1,999	$ 2,303	$ 6,094	$ 6,482
Costs and expenses:
Operating and maintenance expenses	364	389	1,091	1,134
Depreciation and amortization expenses	435	425	1,275	1,290
Selling, general, and administrative expenses	130	174	410	436
Impairment of certain assets (Note 13)	0	0	76	66
Other (income) expense – net	(11)	(6)	30	24
Total costs and expenses	1,371	1,802	4,407	5,080
Operating income (loss)	628	501	1,687	1,402
Equity earnings (losses)	93	105	260	279
Other investing income (loss) – net (Note 5)	(107)	2	(54)	74
Interest incurred	(303)	(286)	(915)	(856)
Interest capitalized	7	16	27	38
Other income (expense) – net	1	52	19	99
Income (loss) before income taxes	319	390	1,024	1,036
Provision (benefit) for income taxes	77	190	244	297
Net income (loss)	242	200	780	739
Less: Net income (loss) attributable to noncontrolling interests	21	71	54	323
Net income (loss) attributable to The Williams Companies, Inc.	221	129	726	416
Preferred stock dividends	1	0	2	0
Net income (loss) available to common stockholders	$ 220	$ 129	$ 724	$ 416
Basic earnings (loss) per common share:
Net income (loss)	$ 0.18	$ 0.13	$ 0.60	$ 0.47
Weighted-average shares (thousands)	1,212,270	1,023,587	1,211,938	893,706
Diluted earnings (loss) per common share:
Net income (loss)	$ 0.18	$ 0.13	$ 0.60	$ 0.46
Weighted-average shares (thousands)	1,214,165	1,026,504	1,213,943	896,322
Service [Member]
Revenues:
Revenues	$ 1,495	$ 1,371	$ 4,424	$ 4,062
NonRegulated Service Commodity Consideration [Member]
Revenues:
Revenues	38	121	158	316
Product [Member]
Revenues:
Revenues	466	811	1,512	2,104
Oil and Gas, Purchased [Member]
Costs and expenses:
Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization	434	790	1,442	2,039
Natural Gas Purchased For Shrink [Member]
Costs and expenses:
Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization	$ 19	$ 30	$ 83	$ 91