Income Taxes	6 Months Ended
	Mar. 31, 2022
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes    The effective tax rates for the quarters ended March 31, 2022 and March 31, 2021 were 25.6% and 26.3%, respectively. The effective tax rates for the six months ended March 31, 2022 and March 31, 2021 were 25.5% and 26.8%, respectively. The decrease in the effective tax rate for the quarter ended March 31, 2022 was primarily due to the realization of the Enhanced Oil Recovery credit in fiscal 2022 that was not available during fiscal 2021. The decrease in the effective tax rate for the six months ended March 31, 2022 was primarily due to differences between the book and tax treatment of equity compensation and the realization of the Enhanced Oil Recovery credit in fiscal 2022, as previously noted.