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- Definition

Current Year

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- Definition

Prior Period, Gross Write-Off

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- Definition

Prior Year

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- Definition

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

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- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-5

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- Definition

Amortized cost excluding accrued interest, of financing receivable originated more than five years prior to current fiscal year. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 79
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479294/326-20-55-79

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

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- Definition

Amortized cost excluding accrued interest, of financing receivable that can be withdrawn, repaid, and redrawn.

+ References

+ Details

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- Definition

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

+ References

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- Definition

Amortized cost excluding accrued interest, of financing receivable originated four years prior to current fiscal year. Excludes net investment in lease.

+ References

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- Definition

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

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- Definition

Amortized cost excluding accrued interest, of financing receivable originated three years prior to current fiscal year. Excludes net investment in lease.

+ References

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- Definition

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

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- Definition

Amortized cost excluding accrued interest, of financing receivable originated in current fiscal year. Excludes net investment in lease.

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- Definition

Amount, excluding accrued interest, of writeoff of financing receivable originated in current fiscal year. Excludes net investment in lease.

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- Definition

Amortized cost excluding accrued interest, of financing receivable originated two years prior to current fiscal year. Excludes net investment in lease.

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

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Amortized cost excluding accrued interest of financing receivable originated in fiscal year prior to current fiscal year. Excludes net investment in lease.

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

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Finance Receivables - Summary of Loans by Risk Rate Grouping (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2025	Dec. 31, 2024	Mar. 31, 2025
Current Period
Total	$ 54,767		$ 54,767		$ 53,042
Current Period, Gross charge-offs
Total	131	$ 111	362	$ 287
Prior Year
Total	54,767		54,767		53,042
Prior Period, Gross charge-offs
Total	131	111	362	287
Dealer loans
Current Period
Total	4,503		4,503		4,344
Current Period, Gross charge-offs
Total	0	0	0	0
Prior Year
Total	4,503		4,503		4,344
Prior Period, Gross charge-offs
Total	0	$ 0	0	$ 0
Dealer loans \| Performing
Current Period
Total	4,503		4,503		4,344
Current Period, Gross charge-offs
Total			0		0
Prior Year
Total	4,503		4,503		4,344
Prior Period, Gross charge-offs
Total			0		0
Dealer loans \| Group I \| Performing
Current Period
Total	3,188		3,188		2,989
Prior Year
Total	3,188		3,188		2,989
Dealer loans \| Group II \| Performing
Current Period
Total	1,314		1,314		1,354
Prior Year
Total	1,314		1,314		1,354
Dealer loans \| Group III \| Performing
Current Period
Total	1		1		1
Prior Year
Total	1		1		1
Dealer loans \| Commercial loans \| Performing
Current Period
2026	46		46		172
2025	151		151		166
2024	161		161		55
2023	52		52		13
2022	13		13		92
Prior	155		155		78
Revolving loans	976		976		762
Current Period, Gross charge-offs
2026			0		0
2025			0		0
2024			0		0
2023			0		0
2022			0		0
Prior			0		0
Revolving loans			0		0
Prior Year
2025	46		46		172
2024	151		151		166
2023	161		161		55
2022	52		52		13
2021	13		13		92
Prior	155		155		78
Revolving loans	976		976		762
Prior Period, Gross charge-offs
2025			0		0
2024			0		0
2023			0		0
2022			0		0
2021			0		0
Prior			0		0
Revolving loans			0		0
Dealer loans \| Commercial loans \| Group I \| Performing
Current Period
2026	38		38		149
2025	134		134		110
2024	105		105		52
2023	50		50		13
2022	8		8		86
Prior	129		129		53
Revolving loans	976		976		762
Prior Year
2025	38		38		149
2024	134		134		110
2023	105		105		52
2022	50		50		13
2021	8		8		86
Prior	129		129		53
Revolving loans	976		976		762
Dealer loans \| Commercial loans \| Group II \| Performing
Current Period
2026	8		8		23
2025	17		17		56
2024	56		56		3
2023	2		2		0
2022	5		5		6
Prior	26		26		25
Revolving loans	0		0		0
Prior Year
2025	8		8		23
2024	17		17		56
2023	56		56		3
2022	2		2		0
2021	5		5		6
Prior	26		26		25
Revolving loans	0		0		0
Dealer loans \| Commercial loans \| Group III \| Performing
Current Period
2026	0		0		0
2025	0		0		0
2024	0		0		0
2023	0		0		0
2022	0		0		0
Prior	0		0		0
Revolving loans	0		0		0
Prior Year
2025	0		0		0
2024	0		0		0
2023	0		0		0
2022	0		0		0
2021	0		0		0
Prior	0		0		0
Revolving loans	0		0		0
Dealer loans \| Wholesale flooring \| Performing
Current Period
Total	2,949		2,949		3,006
Current Period, Gross charge-offs
Total			0		0
Prior Year
Total	2,949		2,949		3,006
Prior Period, Gross charge-offs
Total			0		0
Dealer loans \| Wholesale flooring \| Group I \| Performing
Current Period
Total	1,748		1,748		1,764
Prior Year
Total	1,748		1,748		1,764
Dealer loans \| Wholesale flooring \| Group II \| Performing
Current Period
Total	1,200		1,200		1,241
Prior Year
Total	1,200		1,200		1,241
Dealer loans \| Wholesale flooring \| Group III \| Performing
Current Period
Total	1		1		1
Prior Year
Total	$ 1		$ 1		$ 1