Consolidated Condensed Statements of Comprehensive Income (Parenthetical) (Unaudited) (USD $) In Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Other comprehensive income (loss):
Tax benefit of change in postretirement benefit plans	$ 338	$ 9	$ 315	$ 27
Tax expense of net change in unrealized gains on investment securities	0	3	5	1
Net change in postretirement benefit plans, net of tax:
Tax benefit of amortization of prior service costs (approx.)	1	1	1	1
Tax benefit of amortization of net actuarial loss	12	9	36	27
Tax (expense) benefit of prior service gain from plan amendment	1	0	1	0
Tax (expense) benefit of net actuarial gain (loss) arising during the period	353	0	353	0
Net change in unrealized gains on investment securities, net of tax:
Tax benefit (expense) of unrealized holding (losses) gains arising during period	0	0	1	(2)
Tax expense of gains realized during the period	$ 0	$ 3	$ 6	$ 3