Fair Values of Financial Instruments - Fair Value by Balance Sheet Grouping (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
ASSETS
Debt securities, available-for-sale	$ 8,160,952	$ 9,068,946
Debt securities, trading	909,647	1,077,438
Derivatives, index options	6,071	101,622
Equity securities	22,121	28,217
Carrying Values
ASSETS
Debt securities, available-for-sale	8,160,952	9,068,946
Debt securities, trading	909,647	1,077,438
Cash and cash equivalents	530,559	714,624
Mortgage loans	511,936	487,304
Real estate	28,242	28,606
Policy loans	71,443	71,286
Other loans	21,652	24,266
Derivatives, index options	6,071	101,622
Equity securities	22,121	28,217
Life interest in Libbie Shearn Moody Trust	8,254	8,254
Other investments	4,513	4,537
LIABILITIES
Deferred annuity contracts	6,287,489	6,463,314
Immediate annuity and supplemental contracts	411,053	422,209
Fair Values
ASSETS
Debt securities, available-for-sale	8,160,952	9,068,946
Debt securities, trading	909,647	1,077,438
Cash and cash equivalents	530,559	714,624
Mortgage loans	483,367	513,246
Real estate	48,077	47,027
Policy loans	94,526	110,492
Other loans	22,688	25,085
Derivatives, index options	6,071	101,622
Equity securities	22,121	28,217
Life interest in Libbie Shearn Moody Trust	12,775	12,775
Other investments	26,192	24,876
LIABILITIES
Deferred annuity contracts	5,002,438	4,703,331
Immediate annuity and supplemental contracts	410,039	457,787
Level 1
ASSETS
Debt securities, available-for-sale	0	0
Debt securities, trading	0	0
Cash and cash equivalents	530,559	702,632
Mortgage loans	0	0
Real estate	0	0
Policy loans	0	0
Other loans	0	0
Derivatives, index options	0	0
Equity securities	18,433	23,795
Life interest in Libbie Shearn Moody Trust	0	0
Other investments	0	0
LIABILITIES
Deferred annuity contracts	0	0
Immediate annuity and supplemental contracts	0	0
Level 2
ASSETS
Debt securities, available-for-sale	7,786,995	8,741,984
Debt securities, trading	809,878	1,002,616
Cash and cash equivalents	0	11,992
Mortgage loans	0	0
Real estate	0	0
Policy loans	0	0
Other loans	0	0
Derivatives, index options	0	0
Equity securities	3,688	4,422
Life interest in Libbie Shearn Moody Trust	0	0
Other investments	0	0
LIABILITIES
Deferred annuity contracts	0	0
Immediate annuity and supplemental contracts	0	0
Level 3
ASSETS
Debt securities, available-for-sale	373,957	326,962
Debt securities, trading	99,769	74,822
Cash and cash equivalents	0	0
Mortgage loans	483,367	513,246
Real estate	48,077	47,027
Policy loans	94,526	110,492
Other loans	22,688	25,085
Derivatives, index options	6,071	101,622
Equity securities	0	0
Life interest in Libbie Shearn Moody Trust	12,775	12,775
Other investments	26,192	24,876
LIABILITIES
Deferred annuity contracts	5,002,438	4,703,331
Immediate annuity and supplemental contracts	$ 410,039	$ 457,787

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