General and Summary of Significant Accounting Policies Investments (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Investment Securities, Amortized Cost	$ 19,040	$ 27,661
Other Comprehensive Income (Loss), Securities, Available-for-sale, Adjustment, before Tax	0	0
Investment Securities	19,040	27,661
Short-term Investments [Member]
Debt Securities, Available-for-sale [Line Items]
Investment Securities, Amortized Cost	14,420	14,687
Other Comprehensive Income (Loss), Securities, Available-for-sale, Adjustment, before Tax	0	0
Investment Securities	14,420	14,687
Long-term Investments [Domain]
Debt Securities, Available-for-sale [Line Items]
Investment Securities, Amortized Cost	4,620	12,974
Other Comprehensive Income (Loss), Securities, Available-for-sale, Adjustment, before Tax	0	0
Investment Securities	$ 4,620	$ 12,974

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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