Consolidated Statement of Income (Unaudited) - USD ($) shares in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Revenues:
Revenue from Contract with Customer, Excluding Assessed Tax	$ 2,280		$ 6,423
Service revenues – commodity consideration (Note 2)	121	$ 0	316	$ 0
Total revenues	2,303	1,891	6,482	5,803
Costs and expenses:
Processing commodity expenses (Note 2)	30	0	91	0
Operating and maintenance expenses	389	403	1,134	1,166
Depreciation and amortization expenses	425	433	1,290	1,308
Selling, general, and administrative expenses	174	138	436	452
Gain on sale of Geismar Interest (Note 4)	0	(1,095)	0	(1,095)
Impairment of certain assets (Note 12)	0	1,210	66	1,236
Other (income) expense – net	(6)	24	24	34
Total costs and expenses	1,802	1,617	5,080	4,721
Operating income (loss)	501	274	1,402	1,082
Equity earnings (losses)	105	115	279	347
Other investing income (loss) – net (Note 5)	2	4	74	278
Interest incurred	(286)	(275)	(856)	(842)
Interest capitalized	16	8	38	24
Other income (expense) – net	52	23	99	124
Income (loss) before income taxes	390	149	1,036	1,013
Provision (benefit) for income taxes	190	24	297	126
Net income (loss)	200	125	739	887
Less: Net income (loss) attributable to noncontrolling interests	71	92	323	400
Net income (loss) attributable to The Williams Companies, Inc.	129	33	416	487
Preferred stock dividends (Note 11)	0	0	0	0
Net income (loss) available to common stockholders	$ 129	$ 33	$ 416	$ 487
Basic earnings (loss) per common share:
Net income (loss)	$ 0.13	$ 0.04	$ 0.47	$ 0.59
Weighted-average shares (thousands)	1,023,587	826,779	893,706	825,925
Diluted earnings (loss) per common share:
Net income (loss)	$ 0.13	$ 0.04	$ 0.46	$ 0.59
Weighted-average shares (thousands)	1,026,504	829,368	896,322	828,150
Cash dividends declared per common share	$ 0.34	$ 0.30	$ 1.02	$ 0.9
Service [Member]
Revenues:
Revenue from Contract with Customer, Excluding Assessed Tax	$ 1,371	$ 1,310	$ 4,062	$ 3,853
Product [Member]
Revenues:
Revenue from Contract with Customer, Excluding Assessed Tax	811	581	2,104	1,950
Oil and Gas, Purchased [Member]
Costs and expenses:
Product costs	$ 790	$ 504	$ 2,039	$ 1,620