Summary of Significant Accounting Policies - Shipping and Handling Costs (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Shipping and Handling [Line Items]
Distribution, selling, and administrative	$ 5,661,106	$ 5,309,984	$ 4,848,962
Shipping and Handling
Shipping and Handling [Line Items]
Distribution, selling, and administrative	$ 1,265,700	$ 1,200,000	$ 1,040,800

The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(4))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2

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Balance Type:	debit
Period Type:	duration