Derivatives and Hedging Activities - Additional Information (Details)	9 Months Ended
	Jun. 30, 2020
Minimum
Derivative [Line Items]
Derivative, maturities	1 year
Maximum
Derivative [Line Items]
Derivative, maturities	10 years
Weighted average
Derivative [Line Items]
Derivative, maturities	6 years 10 months 24 days