XML 80 R68.htm IDEA: XBRL DOCUMENT v3.8.0.1
STOCKHOLDERS' EQUITY. (Details) - USD ($)
$ / shares in Units, $ in Millions
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Stockholders' Equity Note [Line Items]      
Common shares authorized for future repurchase (shares) 15,183,779    
Restricted stockholders' equity $ 142    
Regular cash dividend [Member]      
Stockholders' Equity Note [Line Items]      
Cash dividends declared per share $ 2.28 $ 2.16 $ 2.08
Special cash dividend [Member]      
Stockholders' Equity Note [Line Items]      
Cash dividends declared per share     2
Cash dividends paid per share     $ 2