Quarterly Financial Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Quarterly Financial Data [Abstract]
Net sales	$ 4,947	$ 4,697	$ 4,431	$ 4,161	$ 4,558	$ 3,914	$ 4,162	$ 4,151	$ 18,236	$ 16,785	$ 18,372
Gross profit	1,996	1,982	1,862	1,723	1,882	1,618	1,750	1,759	7,563	7,009
Net earnings common stockholders	$ 670	$ 627	$ 561	$ 445	$ 723	$ 399	$ 517	$ 326	$ 2,303	$ 1,965	$ 2,306
Basic earnings per common share	$ 1.12	$ 1.05	$ 0.94	$ 0.74	$ 1.21	$ 0.67	$ 0.85	$ 0.53	$ 3.85	$ 3.26	$ 3.74
Diluted earnings per common share	1.11	1.04	0.93	0.74	1.20	0.67	0.84	0.53	3.82	3.24	3.71
Dividends per common share	$ 0.505	$ 0.505	$ 0.505	$ 0.505	$ 0.50	$ 0.50	$ 0.50	$ 0.50	$ 2.02	$ 2.00	$ 1.96