Condensed Consolidated Statement of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Condensed Consolidated Statement of Comprehensive Income
Net actuarial gains (losses) and amortization of net actuarial (losses) and prior service (cost) and credits, taxes	$ 14	$ 7	$ 39	$ 22
Unrealized gains (losses) on marketable equity securities, taxes	(240)	(5)	104	(7)
Net adjustments for derivative instruments designated as cash flow hedges and other, taxes	$ 2	$ 14	$ 2	$ 12