Cat Financial Financing Activities - Write Offs (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Write-offs by origination year
Total	$ 46	$ 52	$ 134	$ 109
Customer
Write-offs by origination year
2026/2025	1	2	2	2
2025/2024	18	15	40	26
2024/2023	11	16	33	35
2023/2022	9	10	28	22
2022/2021	3	3	13	9
Prior	1	3	8	8
Revolving Finance Receivables	3	3	10	7
Total	46	52	134	109
Customer \| North  America
Write-offs by origination year
2026/2025	1	1	1	1
2025/2024	8	5	16	10
2024/2023	6	7	19	18
2023/2022	5	3	18	9
2022/2021	2	2	8	6
Prior	1	1	6	4
Revolving Finance Receivables	3	2	9	6
Total	26	21	77	54
Customer \| EAME
Write-offs by origination year
2026/2025	0	0	0	0
2025/2024	1	0	4	2
2024/2023	0	3	2	6
2023/2022	2	1	3	2
2022/2021	0	0	1	1
Prior	0	1	1	1
Revolving Finance Receivables	0	1	0	1
Total	3	6	11	13
Customer \| Asia/  Pacific
Write-offs by origination year
2026/2025	0	1	0	1
2025/2024	5	3	9	4
2024/2023	1	1	4	3
2023/2022	1	0	2	1
2022/2021	0	0	1	1
Prior	0	0	0	0
Revolving Finance Receivables	0	0	0	0
Total	7	5	16	10
Customer \| Latin  America
Write-offs by origination year
2026/2025	0	0	1	0
2025/2024	1	2	4	2
2024/2023	3	0	7	2
2023/2022	1	1	5	4
2022/2021	1	1	3	1
Prior	0	0	1	1
Revolving Finance Receivables	0	0	1	0
Total	6	4	22	10
Customer \| Mining
Write-offs by origination year
2026/2025	0	0	0	0
2025/2024	3	5	7	8
2024/2023	1	5	1	6
2023/2022	0	5	0	6
2022/2021	0	0	0	0
Prior	0	1	0	1
Revolving Finance Receivables	0	0	0	0
Total	4	16	8	21
Customer \| Power
Write-offs by origination year
2026/2025				0
2025/2024				0
2024/2023				0
2023/2022				0
2022/2021				0
Prior				1
Revolving Finance Receivables				0
Total				1
Dealer
Write-offs by origination year
Total	$ 0	$ 0	$ 0	$ 0

Write-offs by origination year [Line Items]

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- Definition

Amount of writeoff of financing receivable, charged against allowance for credit loss.

+ References

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- Definition

Amount of writeoff of financing receivable originated more than five years before current fiscal year. Excludes net investment in lease.

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Amount of writeoff of financing receivable that can be withdrawn, repaid, and redrawn.

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Amount of writeoff of financing receivable originated four years before current fiscal year. Excludes net investment in lease.

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Amount of writeoff of financing receivable originated three years before current fiscal year. Excludes net investment in lease.

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Amount of writeoff of financing receivable originated in current fiscal year. Excludes net investment in lease.

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Amount of writeoff of financing receivable originated two years before current fiscal year. Excludes net investment in lease.

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Amount of writeoff of financing receivable originated in fiscal year before current fiscal year. Excludes net investment in lease.

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