Long-term Debt and Other Borrowings - Fair Value of Outstanding Derivatives Designated as Hedging Instruments (Details) - Pay Variable Interest Rate Swap [Member] - USD ($) $ in Millions	Dec. 31, 2019	Sep. 30, 2019
Other assets [Member]
Derivatives, Fair Value [Line Items]
Fair value of outstanding derivative assets designated as hedging instruments in the Consolidated Balance Sheets	$ 45	$ 71
Accounts payable and other liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of outstanding derivative liabilities designated as hedging instruments in the Consolidated Balance Sheets	$ (17)	$ (3)

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- Definition

Fair value as of the balance sheet date of all derivative assets designated as interest rate fair value hedging instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959

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+ References

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