Long-Term Debt and Short-Term Borrowings, Fixed Rate Long-Term Debt (Details) - USD ($) $ in Thousands		12 Months Ended
	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2021
3.24% Senior Notes, due 2050 [Member]
Long-Term Debt [Abstract]
Face value		$ 30,000
Interest rate		3.24%	3.24%
Maturity date		Sep. 30, 2050
Proceeds from debt, net of issuance costs	$ 29,838
10.05% Senior Notes, Series C, due 2020 [Member]
Long-Term Debt [Abstract]
Face value	$ 6,500
Interest rate	10.05%
Maturity date		Sep. 30, 2020