Variable Interest Entities (VIEs) (Narrative) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Variable Interest Entities
Assets	$ 17,492,361	$ 17,266,588
Total liabilities	10,307,230	10,062,667
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entities
Assets	68,999	69,435
Variable Interest Entity, Primary Beneficiary
Variable Interest Entities
Assets	4,503,754	4,564,621
Total liabilities	$ 2,449,879	$ 2,517,652