Long-term Debt and Other Borrowings - Fair Value Hedging - Additional Information (Details) - Senior Notes [Member]	3 Months Ended
	Dec. 31, 2019
Debt Instrument [Line Items]
Weighted-average effective interest rate	3.08%
LIBOR [Member] | Pay Variable Interest Rate Swap [Member]
Debt Instrument [Line Items]
Description of basis spread on variable rate	three-month LIBOR
2022 Notes [Member] | LIBOR [Member] | Pay Variable Interest Rate Swap [Member]
Debt Instrument [Line Items]
Basis spread on variable rate, percentage	0.9486%
2025 Notes [Member] | LIBOR [Member] | Pay Variable Interest Rate Swap [Member]
Debt Instrument [Line Items]
Basis spread on variable rate, percentage	1.1022%
2027 Notes [Member] | LIBOR [Member] | Pay Variable Interest Rate Swap [Member]
Debt Instrument [Line Items]
Basis spread on variable rate, percentage	1.034%
2029 Notes [Member] | LIBOR [Member] | Pay Variable Interest Rate Swap [Member]
Debt Instrument [Line Items]
Basis spread on variable rate, percentage	1.20%