Non-consolidated VIEs - Corporation's VI in non-consolidated VIEs and max exposure to loss (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021	Jun. 30, 2021
Variable Interest Entity
Assets	$ 71,501,931	$ 75,097,899	$ 72,657,293
Variable Interest Entity Not Primary Beneficiary
Variable Interest Entity
Assets	108,016	102,432
Maximum exposure to loss	108,016	102,432
Variable Interest Entity Not Primary Beneficiary | Servicing assets
Variable Interest Entity
Assets	101,094	94,464
Variable Interest Entity Not Primary Beneficiary | Mortgage servicing rights
Variable Interest Entity
Assets	101,094	94,464
Variable Interest Entity Not Primary Beneficiary | Other assets
Variable Interest Entity
Assets	6,922	7,968
Variable Interest Entity Not Primary Beneficiary | Servicing advances
Variable Interest Entity
Assets	$ 6,922	$ 7,968