Employee Benefits (Details 3) (401(k) Plan, USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
401(k) Plan
401(k) Plan
Company common stock included in the assets of the 401(k) Plan (in shares)	9	10
Expenses related to the 401(k) Plan	$ 89	$ 76	$ 70