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, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and financing receivables by origination year, Total	$ 25,064	$ 24,664
Manufactured Housing Loan Balances [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and financing receivables by origination year, 2023	3,280
Loans and financing receivables by origination year, 2022	4,573
Loans and financing receivables by origination year, 2021	3,469
Loans and financing receivables by origination year, 2020	2,704
Loans and financing receivables by origination year, 2019	1,913
Loans and financing receivables by origination year, Prior	7,977
Loans and financing receivables by origination year, Total	23,916
Performing [Member] | Manufactured Housing Loan Balances [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and financing receivables by origination year, 2023	3,273
Loans and financing receivables by origination year, 2022	4,568
Loans and financing receivables by origination year, 2021	3,459
Loans and financing receivables by origination year, 2020	2,694
Loans and financing receivables by origination year, 2019	1,907
Loans and financing receivables by origination year, Prior	7,933
Loans and financing receivables by origination year, Total	23,834
Non-Performing [Member] | Manufactured Housing Loan Balances [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and financing receivables by origination year, 2023	7
Loans and financing receivables by origination year, 2022	5
Loans and financing receivables by origination year, 2021	10
Loans and financing receivables by origination year, 2020	10
Loans and financing receivables by origination year, 2019	6
Loans and financing receivables by origination year, Prior	44
Loans and financing receivables by origination year, Total	$ 82