Investments (Details-4) - ATC [Member] - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Related Party Transaction [Line Items]
Related party expenses	$ 31.4	$ 32.0	$ 30.7
Due from related parties	$ 4.8	$ 7.0

For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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+ Details