Dividends Declared (Detail) - USD ($)
$ / shares in Units, $ in Millions
3 Months Ended 9 Months Ended
Mar. 31, 2016
Dec. 31, 2015
Sep. 30, 2015
Mar. 31, 2015
Dec. 31, 2014
Sep. 30, 2014
Mar. 31, 2016
Mar. 31, 2015
Dividends [Line Items]                
Declaration Date Mar. 15, 2016 Dec. 02, 2015 Sep. 15, 2015 Mar. 10, 2015 Dec. 03, 2014 Sep. 16, 2014    
Dividend Per Share $ 0.36 $ 0.36 $ 0.36 $ 0.31 $ 0.31 $ 0.31 $ 1.08 $ 0.93
Record Date May 19, 2016 Feb. 18, 2016 Nov. 19, 2015 May 21, 2015 Feb. 19, 2015 Nov. 20, 2014    
Total Amount $ 2,833 $ 2,842 $ 2,868 $ 2,515 $ 2,532 $ 2,547    
Payment Date Jun. 09, 2016 Mar. 10, 2016 Dec. 10, 2015 Jun. 11, 2015 Mar. 12, 2015 Dec. 11, 2014