Summary of Investments - Net Investment Gains and Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net investment gains (losses)
Mortgage loans	$ 5	$ (4)	$ (26)
Other long-term investments	2,780	0	0
Real estate	(256)	(28)	(2,150)
Total net investment gains (losses)	47,383	(32,395)	53,779
Proceeds from sales	180,514	50,744	41,760
Continuing Operations
Net investment gains (losses)
Total net investment gains (losses)	47,383	(32,395)	53,779
Fixed maturities
Net investment gains (losses)
Proceeds from sales	180,514	50,744	41,760
Gross realized gains	843	1,400	302
Gross realized losses	(1,120)	(495)	(13)
Available-for-sale \| Fixed maturities
Net investment gains (losses)
Available-for-sale	(277)	1,787	655
Allowance for credit losses \| Fixed maturities
Net investment gains (losses)
Allowance for credit losses	5	(5)	0
Change in fair value
Net investment gains (losses)
Trading securities	0	(3,314)	1,351
Equity securities	30,682	(6,875)	51,231
Sales
Net investment gains (losses)
Trading securities	0	2,950	1,993
Equity securities	$ 14,444	$ (26,906)	$ 725

Amount of expense (reversal of expense) for expected credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), from change in present value of expected cash flows.

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