Consolidated Statement of Comprehensive Income (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Comprehensive income (loss):
Net income (loss)	$ 13us-gaap_ProfitLoss	$ 196us-gaap_ProfitLoss
Other comprehensive income (loss):
Foreign currency translation adjustments, net of taxes	(95)	(44)
Pension and other postretirement benefits:
Amortization of prior service cost (credit) included in net periodic benefit cost, net of taxes	(1)	(1)
Amortization of actuarial (gain) loss included in net periodic benefit cost, net of taxes	7	6
Other comprehensive income (loss)	(89)	(39)
Comprehensive income (loss)	(76)	157
Less: Comprehensive income (loss) attributable to noncontrolling interest	(92)	56
Comprehensive Income (loss) attributable to The Williams Companies, Inc.	$ 16us-gaap_ComprehensiveIncomeNetOfTax	$ 101us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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