Income Taxes (Schedule of Earnings Before Income Taxes and Provision for Income Taxes) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]
United States	$ 6,929	$ 6,461	$ 5,568
Outside United States	13	16	14
Earnings (loss) before income taxes	6,942	6,477	5,582
Current:
Federal - Current	2,066	2,870	2,353
State and local - Current	423	348	275
Outside United States - Current	4	5	4
Total current provision for income taxes	2,493	3,223	2,632
Deferred:
Federal - Deferred	(77)	(920)	(458)
State and local - Deferred	(9)	(9)	15
Total deferred provision for income taxes	(86)	(929)	(443)
Total provision for income taxes	$ 2,407	$ 2,294	$ 2,189