Earnings per Share (EPS) and Common Stock - Additional Information (Details) - USD ($)	3 Months Ended	9 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Sep. 30, 2021
Earnings Per Share And Common Stock [Abstract]
Common stock, shares authorized	500,000,000		500,000,000		500,000,000
Stock repurchase program, authorized amount	$ 1,000,000,000		$ 1,000,000,000
Repurchases of common stock	0	0	1,046,000	0
Stock repurchased during period, value			$ 125,000,000

Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Balance Type:	debit
Period Type:	duration