Condensed Consolidated Statements of Comprehensive Income (Unaudited) (Parentheticals) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Reclassification of losses to net benefit cost, income tax	$ 2	$ 2	$ 4	$ 3
Net derivative instruments gain arising during the period, income tax	$ 16		$ 17
Reclassification of realized derivative instruments (gain) loss to net income, income tax		$ (1)		$ (1)