Consolidated Statement of Comprehensive Income (Loss) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Comprehensive income (loss):
Net income (loss)	$ 1,065	$ 661	$ (922)
Cash flow hedging activities:
Net unrealized gain (loss) from derivative instruments, net of taxes of ($7), ($152), and ($185) in 2012, 2011, and 2010	22	243	303
Reclassifications into earnings of net derivative instruments (gain) loss, net of taxes of $7, $124, and $131 in 2012, 2011, and 2010	(23)	(190)	(211)
Foreign currency translation adjustments	22	(18)	29
Pension and other postretirement benefits:
Prior service credit (cost) arising during the year, net of taxes of ($1) and ($1) in 2012 and 2011	1	1	0
Amortization of prior service cost (credit) included in net periodic benefit cost, net of taxes of $1, $1, and $2 in 2012, 2011 and 2010	(1)	(2)	(2)
Net actuarial gain (loss) arising during the year, net of taxes of $19, $89, and $27 in 2012, 2011, and 2010	(30)	(152)	(56)
Amortization of actuarial (gain) loss included in net periodic benefit cost, net of taxes of ($22), ($16), and ($13) in 2012, 2011, and 2010	39	27	23
Equity securities:
Unrealized gain (loss) on equity securities, net of taxes of ($2) in 2011	0	3	0
Reclassifications into earnings of (gain) loss on sale of equity securities, net of taxes of $2 in 2012	(3)	0	0
Other comprehensive income (loss)	27	(88)	86
Comprehensive income (loss)	1,092	573	(836)
Less: Comprehensive income (loss) attributable to noncontrolling interest	206	285	175
Comprehensive Income (loss) attributable to The Williams Companies, Inc.	$ 886	$ 288	$ (1,011)