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	Jun. 30, 2026	Dec. 31, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and financing receivables by origination year, Total	$ 32,937	$ 31,997
Manufactured Housing Loan Balances [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and financing receivables by origination year, 2026	3,376
Loans and financing receivables by origination year, 2025	4,853
Loans and financing receivables by origination year, 2024	5,167
Loans and financing receivables by origination year, 2023	4,279
Loans and financing receivables by origination year, 2022	3,206
Loans and financing receivables by origination year, Prior	11,451
Loans and financing receivables by origination year, Total	32,332
Performing [Member] \| Manufactured Housing Loan Balances [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and financing receivables by origination year, 2026	3,374
Loans and financing receivables by origination year, 2025	4,841
Loans and financing receivables by origination year, 2024	5,136
Loans and financing receivables by origination year, 2023	4,247
Loans and financing receivables by origination year, 2022	3,191
Loans and financing receivables by origination year, Prior	11,386
Loans and financing receivables by origination year, Total	32,175
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	12
Loans and financing receivables by origination year, 2024	31
Loans and financing receivables by origination year, 2023	32
Loans and financing receivables by origination year, 2022	15
Loans and financing receivables by origination year, Prior	65
Loans and financing receivables by origination year, Total	$ 157

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.

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