Investment Securities (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Cost
Equity	$ 310,055	$ 304,305
Debt	792,554	774,580
Other	7,134	19,102
Total	1,109,743	1,097,987
Gains
Equity	236,875	280,127
Debt	446	4,859
Other	0	0
Total	237,321	284,986
Losses
Equity	(4,239)	(4,682)
Debt	(24,757)	(7,001)
Other	0	(1)
Total	(28,996)	(11,684)
Fair Value
Equity	542,691	579,750
Debt	768,243	772,438
Other	7,134	19,101
Total	$ 1,318,068	$ 1,371,289

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