Variable Interest Entities (Schedule of Aggregate Assets, Liabilities, and Our Exposure to Loss from those VIEs) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Dec. 31, 2021
Variable Interest Entity [Line Items]
Assets	$ 37,612,063	$ 34,049,715
Total liabilities	32,384,713	$ 29,014,756
Variable Interest Entity Not Primary Beneficiary [Member] | Debt and equity [member]
Variable Interest Entity [Line Items]
Assets	835,641
Total liabilities	373,002
Gain (Loss) on Price Risk Derivatives, Net	56,083
Variable Interest Entity Not Primary Beneficiary [Member] | Miscellaneous Investments [Member]
Variable Interest Entity [Line Items]
Assets	460,093
Total liabilities	371,047
Gain (Loss) on Price Risk Derivatives, Net	56,083
Variable Interest Entity Not Primary Beneficiary [Member] | Partnership Interest [Member]
Variable Interest Entity [Line Items]
Assets	375,548
Total liabilities	1,955
Gain (Loss) on Price Risk Derivatives, Net	$ 0