Loans and finance receivables - Summary of performing and non-performing home loans before discounts and allowances by year of loan origination (Detail) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and financing receivables by origination year, Total	$ 32,270	$ 31,997
Manufactured Housing Loan Balances [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and financing receivables by origination year, 2026	1,844
Loans and financing receivables by origination year, 2025	4,963
Loans and financing receivables by origination year, 2024	5,302
Loans and financing receivables by origination year, 2023	4,402
Loans and financing receivables by origination year, 2022	3,287
Loans and financing receivables by origination year, Prior	11,811
Loans and financing receivables by origination year, Total	31,609
Performing [Member] \| Manufactured Housing Loan Balances [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and financing receivables by origination year, 2026	1,842
Loans and financing receivables by origination year, 2025	4,953
Loans and financing receivables by origination year, 2024	5,270
Loans and financing receivables by origination year, 2023	4,371
Loans and financing receivables by origination year, 2022	3,267
Loans and financing receivables by origination year, Prior	11,730
Loans and financing receivables by origination year, Total	31,433
Non-Performing [Member] \| Manufactured Housing Loan Balances [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and financing receivables by origination year, 2026	2
Loans and financing receivables by origination year, 2025	10
Loans and financing receivables by origination year, 2024	32
Loans and financing receivables by origination year, 2023	31
Loans and financing receivables by origination year, 2022	20
Loans and financing receivables by origination year, Prior	81
Loans and financing receivables by origination year, Total	$ 176

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
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-URI https://asc.fasb.org/1943274/2147481990/310-10-45-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2003/role/exampleRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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