Segment Information (Geographical Revenue Information) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues	$ 6,087	$ 5,641	$ 5,465	$ 9,043	$ 7,700	$ 6,332	$ 4,565	$ 7,525	$ 26,236	$ 26,122	$ 21,733
U.S. [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues									20,688	21,814	21,561
Japan [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues									5,548	4,363	135
Other Category [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Revenues									$ 0	$ (55)	$ 37