Segment and Other Operating Information - Net Earnings (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Segment Reporting Information [Line Items]
Net earnings	$ 36,184	$ 62,129
Segments
Segment Reporting Information [Line Items]
Net earnings	33,186	61,010
Segment Reconciling Items
Segment Reporting Information [Line Items]
Realized gains on investments, net of taxes	$ 2,998	$ 1,119

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details