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Inventories - Narrative (Detail) - USD ($) $ in Billions | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Railroad, Utilities and Energy [Member] | Other Assets [Member] |  |
Inventory [Line Items] |  |
Inventory, materials and supplies | $ 3.0 | $ 3.0

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- Definition Aggregated amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed. This amount is net of valuation reserves and adjustments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 330 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.BB) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480581/330-10-S99-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(6)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
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