Commitments and Contingent Liabilities Variable Interest Entities (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Variable Interest Entity [Line Items]
Liabilities	$ 40,715,451	$ 37,308,102
Other Assets [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity, Nonconsolidated Entities, Assets	260,000
Other Liabilities [Member] | Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Liabilities	$ 78,000