Fair Values of Financial Instruments (Fair Value by Balance Sheet Grouping) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
ASSETS
Debt securities held to maturity	$ 7,181,687	$ 7,407,703
Debt securities, available for sale	3,174,260	3,356,945
Derivatives, index options	24,335	157,588
Equity securities	15,984	23,594
Carrying Values
ASSETS
Debt securities held to maturity	6,990,041	7,106,245
Debt securities, available for sale	3,174,260	3,356,945
Cash and cash equivalents	352,215	253,524
Mortgage loans	276,083	272,422
Real estate	34,443	34,588
Policy loans	78,036	80,008
Other loans	13,461	13,547
Derivatives, index options	24,335	157,588
Equity securities	15,984	23,594
Life interest in Libbie Shearn Moody Trust	9,230	9,230
Other investments	4,515	197
LIABILITIES
Deferred annuity contracts	6,866,418	7,014,833
Immediate annuity and supplemental contracts	399,448	400,465
Contingent consideration on businesses acquired	4,174	4,076
Fair Values
ASSETS
Debt securities held to maturity	7,181,687	7,407,703
Debt securities, available for sale	3,174,260	3,356,945
Cash and cash equivalents	352,215	253,524
Mortgage loans	278,015	270,931
Real estate	48,547	57,204
Policy loans	135,870	123,650
Other loans	13,643	13,698
Derivatives, index options	24,335	157,588
Equity securities	15,984	23,594
Life interest in Libbie Shearn Moody Trust	12,775	12,775
Other investments	22,582	16,182
LIABILITIES
Deferred annuity contracts	5,760,527	5,931,352
Immediate annuity and supplemental contracts	449,249	422,931
Contingent consideration on businesses acquired	4,174	4,076
Level 1
ASSETS
Debt securities held to maturity	0	0
Debt securities, available for sale	0	0
Cash and cash equivalents	352,215	253,524
Mortgage loans	0	0
Real estate		0
Policy loans	0	0
Other loans	0	0
Derivatives, index options	0	0
Equity securities	15,984	23,594
Life interest in Libbie Shearn Moody Trust	0	0
Other investments	2	2
LIABILITIES
Deferred annuity contracts	0	0
Immediate annuity and supplemental contracts	0	0
Contingent consideration on businesses acquired	0	0
Level 2
ASSETS
Debt securities held to maturity	7,181,687	7,407,703
Debt securities, available for sale	3,174,260	3,356,945
Cash and cash equivalents	0	0
Mortgage loans	0	0
Real estate		0
Policy loans	0	0
Other loans	0	0
Derivatives, index options	0	0
Equity securities	0	0
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
Contingent consideration on businesses acquired	0	0
Level 3
ASSETS
Debt securities held to maturity		0
Debt securities, available for sale	0	0
Cash and cash equivalents	0	0
Mortgage loans	278,015	270,931
Real estate	48,547	57,204
Policy loans	135,870	123,650
Other loans	13,643	13,698
Derivatives, index options	24,335	157,588
Equity securities	0	0
Life interest in Libbie Shearn Moody Trust	12,775	12,775
Other investments	22,580	16,180
LIABILITIES
Deferred annuity contracts	5,760,527	5,931,352
Immediate annuity and supplemental contracts	449,249	422,931
Contingent consideration on businesses acquired	$ 4,174	4,076
Restatement adjustment
LIABILITIES
Increase in future policy benefits liability		$ 15,000

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