Consolidated Statements Of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Statement of Comprehensive Income [Abstract]
Net Income Available for Common Stock	$ 133,020	$ 169,689
Other Comprehensive Income (Loss), Before Tax:
Unrealized Gain (Loss) on Derivative Financial Instruments Arising During the Period	189,167	297,593
Reclassification Adjustment for Realized (Gains) Losses on Derivative Financial Instruments in Net Income	(19,708)	159,342
Other Comprehensive Income (Loss), Before Tax	169,459	456,935
Income Tax Expense (Benefit) Related to Unrealized Gain (Loss) on Derivative Financial Instruments Arising During the Period	52,486	81,377
Reclassification Adjustment for Income Tax Benefit (Expense) on Realized Losses (Gains) from Derivative Financial Instruments in Net Income	(5,468)	43,571
Income Taxes – Net	47,018	124,948
Other Comprehensive Income (Loss)	122,441	331,987
Comprehensive Income	$ 255,461	$ 501,676