XML 15 R4.htm IDEA: XBRL DOCUMENT v3.10.0.1
Consolidated Balance Sheet and Mini Balance Sheet (Paranthetical) - USD ($)
$ in Millions
Sep. 30, 2018
Dec. 31, 2017
Condensed Balance Sheet Statements, Captions [Line Items]    
Common stock, par value $ 0.01 $ 0.01
Common stock, authorized 1,100,000,000 1,100,000,000
Common stock, issued 492,366,900 489,883,553
Common stock, outstanding   437,053,936
Treasury stock, shares 75,776,392 52,829,617
Debt securities, held-to-maturity, fair value $ 2,139 $ 1,865
End of period    
Condensed Balance Sheet Statements, Captions [Line Items]    
Common stock, outstanding 416,590,508 437,054,000