Investment Securities (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2023	Dec. 31, 2022
Cost
Equity	$ 330,886	$ 323,907
Debt	843,576	833,035
Other	6,006	10,445
Total	1,180,468	1,167,387
Gains
Equity	209,975	159,445
Debt	1,057	372
Other	59	20
Total	211,091	159,837
Losses
Equity	(6,023)	(8,949)
Debt	(39,246)	(46,369)
Other	(7)	(9)
Total	(45,276)	(55,327)
Fair Value
Equity	534,838	474,403
Debt	805,387	787,038
Other	6,058	10,456
Total	$ 1,346,283	$ 1,271,897

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