Consolidated Balance Sheets (Parenthetical) - $ / shares $ / shares in Millions	Dec. 31, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Common stock, par value	$ 0	$ 0
Common stock, shares authorized	2,000,000,000	2,000,000,000
Common stock, shares outstanding	968,187,955	963,335,888
Treasury stock, shares held	2,000,000	2,000,000