Consolidated Statement of Comprehensive Income (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Comprehensive income (loss):
Net income (loss)	$ 203	$ 342	$ 863	$ 1,023
Cash flow hedging activities:
Net unrealized gain (loss) from derivative instruments, net of taxes of $3 and ($9) in 2012 and ($79) and ($100) in 2011	(9)	124	25	155
Reclassifications into earnings of net derivative instruments (gain) loss, net of taxes of $3 and $5 in 2012 and $30 and $83 in 2011	(11)	(41)	(15)	(126)
Foreign currency translation adjustments	30	(66)	32	(39)
Pension and other postretirement benefits:
Amortization of prior service cost (credit) included in net periodic benefit expense, net of taxes of $1 and $1 in 2011	0	0	(1)	(1)
Net actuarial gain (loss) arising during the year, net of taxes of $1 and $2 in 2012 and $2 and $2 in 2011	(1)	(4)	(4)	(4)
Amortization of actuarial (gain) loss included in net periodic benefit expense, net of taxes of ($6) and ($17) in 2012 and ($5) and ($12) in 2011	10	9	29	21
Equity securities:
Unrealized gain (loss) on equity securities, net of taxes of ($1) in 2011	0	(1)	0	2
Reclassifications into earnings of (gain) loss on sale of equity securities, net of taxes of $2 in 2012	0	0	(3)	0
Other comprehensive income (loss)	19	21	63	8
Comprehensive income (loss)	222	363	926	1,031
Less: Comprehensive income (loss) attributable to noncontrolling interest	40	70	157	203
Comprehensive Income (loss) attributable to The Williams Companies, Inc.	$ 182	$ 293	$ 769	$ 828