Allowance for credit losses - Troubled debt restructuring according to their accruing status - Subnote (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Financing Receivable, Modifications [Line Items]
Financing Receivable Modifications Recorded Investment	$ 1,644,647	$ 1,656,822
Accruing
Financing Receivable, Modifications [Line Items]
Financing Receivable Modifications Recorded Investment	1,495,309	1,468,966
Mortgages
Financing Receivable, Modifications [Line Items]
Financing Receivable Modifications Recorded Investment	1,256,766	1,255,713
Mortgages | Accruing
Financing Receivable, Modifications [Line Items]
Financing Receivable Modifications Recorded Investment	1,169,976	1,143,204
Mortgages | Guaranteed by U.S. sponsored entities | Accruing
Financing Receivable, Modifications [Line Items]
Financing Receivable Modifications Recorded Investment	$ 725,000	$ 716,000