Consolidated Statement of Changes in Equity (Unaudited) - USD ($) $ in Millions	Total	Total Stockholders’ Equity	Preferred Stock	Common Stock	Capital in Excess of Par Value	Retained Deficit	AOCI	Treasury Stock	Noncontrolling Interests
Period Start at Dec. 31, 2017	$ 16,175	$ 9,656	$ 0	$ 861	$ 18,508	$ (8,434)	$ (238)	$ (1,041)	$ 6,519
Adoption of new accounting standards	(121)	(84)	0	0	0	(23)	(61)	0	(37)
Net income (loss)	739	416	0	0	0	416	0	0	323
Other comprehensive income (loss)	9	11	0	0	0	0	11	0	(2)
WPZ Merger (Note 1)	1,862	6,491	0	382	6,112	0	(3)	0	(4,629)
Issuance of preferred stock (Note 12)	35	35	35	0	0	0	0	0	0
Cash dividends – common stock	(974)	(974)	0	0	0	(974)	0	0	0
Dividends and distributions to noncontrolling interests	(598)	0	0	0	0	0	0	0	(598)
Stock-based compensation and related common stock issuances, net of tax	49	49	0	1	48	0	0	0	0
Sales of limited partner units of Williams Partners L.P.	46	0	0	0	0	0	0	0	46
Changes in ownership of consolidated subsidiaries, net	(4)	14	0	0	14	0	0	0	(18)
Contributions from noncontrolling interests	13	0	0	0	0	0	0	0	13
Deconsolidation of subsidiary (Note 5)	267	0	0	0	0	0	0	0	267
Other	(5)	(4)	0	1	(2)	(3)	0	0	(1)
Net increase (decrease) in equity	784	5,954	35	384	6,172	(584)	(53)	0	(5,170)
Period End at Sep. 30, 2018	16,959	15,610	35	1,245	24,680	(9,018)	(291)	(1,041)	1,349
Period Start at Jun. 30, 2018	15,447	9,345	0	862	18,552	(8,735)	(293)	(1,041)	6,102
Net income (loss)	200	129	0	0	0	129	0	0	71
Other comprehensive income (loss)	6	5	0	0	0	0	5	0	1
WPZ Merger (Note 1)	1,862	6,491	0	382	6,112	0	(3)	0	(4,629)
Issuance of preferred stock (Note 12)	35	35	35	0	0	0	0	0	0
Cash dividends – common stock	(411)	(411)	0	0	0	(411)	0	0	0
Dividends and distributions to noncontrolling interests	(196)	0	0	0	0	0	0	0	(196)
Stock-based compensation and related common stock issuances, net of tax	16	16	0	0	16	0	0	0	0
Changes in ownership of consolidated subsidiaries, net	0	1	0	0	1	0	0	0	(1)
Contributions from noncontrolling interests	2	0	0	0	0	0	0	0	2
Deconsolidation of subsidiary (Note 5)			0
Other	(2)	(1)		1	(1)	(1)	0	0	(1)
Net increase (decrease) in equity	1,512	6,265	35	383	6,128	(283)	2	0	(4,753)
Period End at Sep. 30, 2018	16,959	15,610	35	1,245	24,680	(9,018)	(291)	(1,041)	1,349
Period Start at Dec. 31, 2018	15,997	14,660	35	1,245	24,693	(10,002)	(270)	(1,041)	1,337
Net income (loss)	780	726	0	0	0	726	0	0	54
Other comprehensive income (loss)	4	4	0	0	0	0	4	0	0
Cash dividends – common stock	(1,382)	(1,382)	0	0	0	(1,382)	0	0	0
Dividends and distributions to noncontrolling interests	(86)	0	0	0	0	0	0	0	(86)
Stock-based compensation and related common stock issuances, net of tax	45	45	0	2	43	0	0	0	0
Sale of partial interest in consolidated subsidiary (Note 2)	1,333	0	0	0	0	0	0	0	1,333
Changes in ownership of consolidated subsidiaries, net	142	(426)	0	0	(426)	0	0	0	568
Contributions from noncontrolling interests	32	0	0	0	0	0	0	0	32
Other	(6)	(6)	0	0	0	(6)	0	0	0
Net increase (decrease) in equity	862	(1,039)	0	2	(383)	(662)	4	0	1,901
Period End at Sep. 30, 2019	16,859	13,621	35	1,247	24,310	(10,664)	(266)	(1,041)	3,238
Period Start at Jun. 30, 2019	17,081	13,848	35	1,246	24,296	(10,423)	(265)	(1,041)	3,233
Net income (loss)	242	221	0	0	0	221	0	0	21
Other comprehensive income (loss)	(1)	(1)	0	0	0	0	(1)	0	0
Cash dividends – common stock	(461)	(461)	0	0	0	(461)	0	0	0
Dividends and distributions to noncontrolling interests	(18)	0	0	0	0	0	0	0	(18)
Stock-based compensation and related common stock issuances, net of tax	17	17	0	1	16	0	0	0	0
Changes in ownership of consolidated subsidiaries, net	1	(1)	0	0	(1)	0	0	0	2
Other	(2)	(2)	0	0	(1)	(1)	0	0	0
Net increase (decrease) in equity	(222)	(227)	0	1	14	(241)	(1)	0	5
Period End at Sep. 30, 2019	$ 16,859	$ 13,621	$ 35	$ 1,247	$ 24,310	$ (10,664)	$ (266)	$ (1,041)	$ 3,238