General and Summary of Significant Accounting Policies Investments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Current	$ 501	$ 4,224
Investment Securities, Amortized Cost	501	4,740
Investment Securities	501	4,740
Short-term investment securities	501	4,224
Long-term Investment Securities	0	516
Debt Securities, Available-for-Sale, Unrealized Loss	0	0
Corporate Debt Securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Current	501	2,314
Short-term investment securities	501	2,314
Debt Securities, Available-for-Sale, Amortized Cost, Noncurrent	0	516
Long-term Investment Securities	0	516
Debt Securities, Available-for-Sale, Unrealized Loss	0	0
US Treasury Securities
Debt Securities, Available-for-sale [Line Items]
Short-term investment securities	0	1,412
Debt Securities, Available-for-Sale, Unrealized Loss	0	0
US Treasury Securities | Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-sale [Line Items]
Short-term investment securities	0	1,412
US Government Debt Securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Current	0	498
Short-term investment securities	0	498
Debt Securities, Available-for-Sale, Unrealized Loss	$ 0	0
US Government Debt Securities | Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-sale [Line Items]
Short-term investment securities		$ 0