Consolidated Statements of Comprehensive Income (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net income	$ 3,501us-gaap_ProfitLoss	$ 2,135us-gaap_ProfitLoss	$ 2,645us-gaap_ProfitLoss
Other comprehensive income, net of income taxes:
Defined benefit and other postretirement plans adjustments	(84)	0	(33)
Other	(7)	2	(3)
Other comprehensive income (loss), net of income taxes	(92)	2	(36)
Comprehensive income	3,410	2,137	2,609
Comprehensive income attributable to noncontrolling interest	(1)	(10)	(10)
Comprehensive income attributable to company shareholders	$ 3,409us-gaap_ComprehensiveIncomeNetOfTax	$ 2,127us-gaap_ComprehensiveIncomeNetOfTax	$ 2,599us-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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