Shareholders' Equity - Schedule of AOCI (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Shareholders' equity, beginning balance	$ 7,906,889	$ 6,791,203
Other comprehensive loss before reclassifications	(46,691)	58,979
Amounts reclassified from accumulated other comprehensive income	744	1,142
Net current-period other comprehensive loss	(45,947)	60,121
Shareholders' equity, ending balance	8,289,545	7,213,156
Available- for-Sale Securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Shareholders' equity, beginning balance	47	238
Other comprehensive loss before reclassifications	(69)	(63)
Amounts reclassified from accumulated other comprehensive income	0	0
Net current-period other comprehensive loss	(69)	(63)
Shareholders' equity, ending balance	(22)	175
Interest Rate Agreement Cash Flow Hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Shareholders' equity, beginning balance	69,756	(57,827)
Other comprehensive loss before reclassifications	(46,622)	59,042
Amounts reclassified from accumulated other comprehensive income	744	1,142
Net current-period other comprehensive loss	(45,878)	60,184
Shareholders' equity, ending balance	23,878	2,357
Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Shareholders' equity, beginning balance	69,803	(57,589)
Net current-period other comprehensive loss	(45,947)	60,121
Shareholders' equity, ending balance	$ 23,856	$ 2,532