Earnings Per Share - Earnings Per Share (Detail) - USD ($) shares in Millions, $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Earnings Per Share [Abstract]
Income from continuing operations	$ 379	$ 574	$ 771	$ 1,244
Income from discontinued operations	0	0	0	124
Basic and diluted income (loss) available to shareholders	$ 379	$ 574	$ 771	$ 1,368
Weighted Average Shares Outstanding
Basic weighted average shares outstanding	692.2	714.5	698.6	718.2
Effect of dilutive securities:
Stock options, unvested restricted stock and unvested performance share awards	2.7	5.2	3.8	4.3
Diluted weighted average shares outstanding	694.9	719.7	702.4	722.5
Antidilutive Securities
Options to purchase shares	0.6	0.0	0.3	0.1

Antidilutive securities.

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Effect Of Dilutive Securities [Abstract]

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Amount after tax of income (loss) from continuing operations attributable to the parent.

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