Benefit Plans (Summary of the components of net periodic benefit cost recognized for pension plans) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 150	$ 120	$ 105
Interest cost	120	110	103
Estimated return on plan assets	(257)	(200)	(197)
Net Amortization and other	91	76	34
Net periodic benefit cost	104	106	45
Net actuarial loss (gain)	(535)	270	388
Net amortization	(91)	(76)	(34)
Net amount recognized in OCI	(626)	194	354
Total net periodic pension costs (income) recognized in total comprehensive income, pre-tax	(522)	300	399
Qualified Pension Plan [Member}
Defined Benefit Plan Disclosure [Line Items]
Service cost	139	113
Interest cost	107	100
Nonqualified Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	11	7
Interest cost	$ 12	$ 10