Shareholders' Equity - Schedule of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2024	Mar. 31, 2023
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Shareholders' equity, beginning balance	$ 11,273,209	$ 10,870,064	$ 9,836,274	$ 9,419,091	$ 10,870,064	$ 9,419,091
Other comprehensive income (loss) before reclassifications					(17,845)	(7,055)
Amounts reclassified from accumulated other comprehensive income					(4,983)	(1,060)
Total other comprehensive income (loss)	27,108	(49,936)	(30,333)	22,218	(22,828)	(8,115)
Shareholders' equity, ending balance	11,618,639	11,273,209	10,205,205	9,836,274	11,618,639	10,205,205
Available- for-Sale Securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Shareholders' equity, beginning balance		(369)		(495)	(369)	(495)
Other comprehensive income (loss) before reclassifications					246	221
Amounts reclassified from accumulated other comprehensive income					0	0
Total other comprehensive income (loss)					246	221
Shareholders' equity, ending balance	(123)		(274)		(123)	(274)
Interest Rate Agreement Cash Flow Hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Shareholders' equity, beginning balance		518,897		369,607	518,897	369,607
Other comprehensive income (loss) before reclassifications					(18,091)	(7,276)
Amounts reclassified from accumulated other comprehensive income					(4,983)	(1,060)
Total other comprehensive income (loss)					(23,074)	(8,336)
Shareholders' equity, ending balance	495,823		361,271		495,823	361,271
Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Shareholders' equity, beginning balance	468,592	518,528	391,330	369,112	518,528	369,112
Total other comprehensive income (loss)	27,108	(49,936)	(30,333)	22,218
Shareholders' equity, ending balance	$ 495,700	$ 468,592	$ 360,997	$ 391,330	$ 495,700	$ 360,997