Allowance for credit losses - Troubled debt restructuring according to their accruing status - Subnote (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Financing Receivable
Financing Receivable Modifications Recorded Investment	$ 1,640,640	$ 1,656,822
Accruing
Financing Receivable
Financing Receivable Modifications Recorded Investment	1,488,548	1,468,966
Mortgages
Financing Receivable
Financing Receivable Modifications Recorded Investment	1,253,001	1,255,713
Mortgages | Accruing
Financing Receivable
Financing Receivable Modifications Recorded Investment	1,167,237	1,143,204
Mortgages | Guaranteed by U.S. sponsored entities | Accruing
Financing Receivable
Financing Receivable Modifications Recorded Investment	$ 725,000	$ 716,000