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, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and financing receivables by origination year, Total	$ 27,792	$ 26,289
Manufactured Housing Loan Balances [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and financing receivables by origination year, 2024	3,481
Loans and financing receivables by origination year, 2023	5,213
Loans and financing receivables by origination year, 2022	3,822
Loans and financing receivables by origination year, 2021	3,199
Loans and financing receivables by origination year, 2020	2,476
Loans and financing receivables by origination year, Prior	8,758
Loans and financing receivables by origination year, Total	26,949
Performing [Member] \| Manufactured Housing Loan Balances [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and financing receivables by origination year, 2024	3,479
Loans and financing receivables by origination year, 2023	5,207
Loans and financing receivables by origination year, 2022	3,814
Loans and financing receivables by origination year, 2021	3,189
Loans and financing receivables by origination year, 2020	2,468
Loans and financing receivables by origination year, Prior	8,715
Loans and financing receivables by origination year, Total	26,872
Non-Performing [Member] \| Manufactured Housing Loan Balances [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and financing receivables by origination year, 2024	2
Loans and financing receivables by origination year, 2023	6
Loans and financing receivables by origination year, 2022	8
Loans and financing receivables by origination year, 2021	10
Loans and financing receivables by origination year, 2020	8
Loans and financing receivables by origination year, Prior	43
Loans and financing receivables by origination year, Total	$ 77

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