Revenue Recognition - Contract Balances (Details) - USD ($) $ in Millions	Mar. 31, 2023	Sep. 30, 2022
Disaggregation of Revenue [Line Items]
Contract liabilities - current	$ 1,939	$ 1,768
Accounts receivable - net
Disaggregation of Revenue [Line Items]
Contract assets - current	2,026	2,020
Other noncurrent assets
Disaggregation of Revenue [Line Items]
Contract assets - noncurrent	81	79
Deferred revenue
Disaggregation of Revenue [Line Items]
Contract liabilities - current	1,939	1,768
Other noncurrent liabilities
Disaggregation of Revenue [Line Items]
Contract liabilities - noncurrent	$ 292	$ 282

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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