Basis Of Presentation Basis of Presentation (Narrative) (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Jun. 30, 2016
Summary Of Significant Accounting Policies [Line Items]
Stock Issued During Period, Shares, New Issues	6.0	13.8
Proceeds from issuance of common stock, net of issuance costs	$ 937	$ 1,600	$ 0	$ 2,534