Income Taxes Reconciliation of the beginning and ending amount of unrecognized tax benefits (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Reconciliation of the Company's beginning and ending amount of unrecognized tax benefits
Balance at the beginning of the period	$ 156	$ 118
Additions based on tax positions related to the current year	22	21
Additions for tax positions of prior years	69	45
Reductions for tax positions of prior years	(70)	(1)
Settlements	(10)	(22)
Lapse of statute of limitations	(3)	(5)
Balance at the end of the period	$ 164	$ 156