Variable Interest Entity - Schedule of Assets and Liabilities of Profarma (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Variable Interest Entity [Line Items]
Cash and cash equivalents	$ 3,297,880	$ 2,752,889	$ 3,593,539	$ 3,070,128
Inventories	18,998,833	17,454,768
Property and equipment, net	2,181,410	2,135,171
Other long-term assets	3,637,023	3,418,182
TOTAL ASSETS	67,101,667	62,558,746
Long-term debt	4,388,076	4,787,457
Deferred income taxes	1,643,746	1,657,944
Other long-term liabilities	1,993,683	1,884,733
Profarma
Variable Interest Entity [Line Items]
Cash and cash equivalents	58,082	33,256
Accounts receivables, net	236,930	253,419
Inventories	259,299	255,801
Prepaid expenses and other	68,612	63,327
Property and equipment, net	49,869	42,759
Other intangible assets	58,116	62,384
Other long-term assets	83,765	77,889
TOTAL ASSETS	814,673	788,835
Accounts payable	307,201	300,875
Accrued expenses and other	56,597	56,280
Short-term debt	76,308	73,650
Long-term debt	91,246	74,132
Deferred income taxes	19,227	22,701
Other long-term liabilities	61,690	54,691
Total liabilities	$ 612,269	$ 582,329