Nonconsolidated Partially-Owned Affiliates - Income Statement (Details) - USD ($) $ in Millions	6 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Equity Method Investments and Joint Ventures [Abstract]
Net sales	$ 8,127	$ 9,273
Gross profit	958	1,086
Net income	336	436
Net income attributable to the entity	$ 326	$ 405

Equity Method Investments Summarized Financial Information Net Income (Loss) Including Noncontrolling Interests

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- Definition

The amount of gross profit (loss) reported by an equity method investment of the entity.

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- Definition

The amount of net income (loss) reported by an equity method investment of the entity.

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The amount of revenue from sale of goods and services reduced by sales returns, allowances, and discounts reported by an equity method investment of the entity.

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