Consolidated Statement of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Comprehensive income (loss):
Net income (loss)	$ 125	$ 131	$ 887	$ (387)
Cash flow hedging activities:
Net unrealized gain (loss) from derivative instruments, net of taxes of $2 and $1 in 2017	(9)	2	(5)	2
Reclassifications into earnings of net derivative instruments (gain) loss, net of taxes of $1 and $1 in 2017	2	0	0	0
Foreign currency translation activities:
Foreign currency translation adjustments, net of taxes of ($25) and ($37) in 2016	0	(49)	0	50
Reclassification into earnings upon sale of foreign entity, net of taxes of ($36) in 2016	0	119	0	119
Pension and other postretirement benefits:
Amortization of prior service cost (credit) included in net periodic benefit cost, net of taxes of $1 and $2 in 2017 and $0 and $1 in 2016	0	(1)	(2)	(3)
Net actuarial gain (loss) arising during the year, net of taxes of $2 in 2016	0	0	0	(3)
Amortization of actuarial (gain) loss included in net periodic benefit cost, net of taxes of ($2) and ($7) in 2017 and ($3) and ($9) in 2016	4	5	13	15
Other comprehensive income (loss)	(3)	76	6	180
Comprehensive income (loss)	122	207	893	(207)
Less: Comprehensive income (loss) attributable to noncontrolling interests	89	108	398	91
Comprehensive income (loss) attributable to The Williams Companies, Inc.	$ 33	$ 99	$ 495	$ (298)