Fair Values of Financial Instruments (Fair Value by Balance Sheet Grouping) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019
ASSETS
Debt securities held to maturity	$ 7,432,702		$ 7,407,703
Debt securities available for sale	3,373,113		3,356,945
Derivatives, index options	66,738		157,588
Equity securities	17,918		23,594
LIABILITIES
Contingent consideration on businesses acquired		$ 4,200
Carrying Values
ASSETS
Debt securities held to maturity	6,898,842		7,106,245
Debt securities available for sale	3,373,113		3,356,945
Cash and cash equivalents	450,703		253,524
Mortgage loans	273,701		272,422
Real estate	34,298		34,588
Policy loans	76,811		80,008
Other loans	18,064		13,547
Derivatives, index options	66,738		157,588
Equity securities	17,918		23,594
Life interest in Libbie Shearn Moody Trust	9,230		9,230
Other investments	4,515		197
LIABILITIES
Deferred annuity contracts	6,755,394		7,014,833
Immediate annuity and supplemental contracts	403,856		400,465
Contingent consideration on businesses acquired	0		4,076
Fair Values
ASSETS
Debt securities held to maturity	7,432,702		7,407,703
Debt securities available for sale	3,373,113		3,356,945
Cash and cash equivalents	450,703		253,524
Mortgage loans	272,336		270,931
Real estate	48,547		57,204
Policy loans	132,257		123,650
Other loans	18,365		13,698
Derivatives, index options	66,738		157,588
Equity securities	17,918		23,594
Life interest in Libbie Shearn Moody Trust	12,775		12,775
Other investments	22,582		16,182
LIABILITIES
Deferred annuity contracts	5,511,416		5,931,352
Immediate annuity and supplemental contracts	455,875		422,931
Contingent consideration on businesses acquired	0		4,076
Level 1
ASSETS
Debt securities held to maturity	0		0
Debt securities available for sale	0		0
Cash and cash equivalents	450,703		253,524
Mortgage loans	0		0
Real estate	0		0
Policy loans	0		0
Other loans	0		0
Derivatives, index options	0		0
Equity securities	17,918		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	7,432,702		7,407,703
Debt securities available for sale	3,373,113		3,356,945
Cash and cash equivalents	0		0
Mortgage loans	0		0
Real estate	0		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		0
Debt securities available for sale	0		0
Cash and cash equivalents	0		0
Mortgage loans	272,336		270,931
Real estate	48,547		57,204
Policy loans	132,257		123,650
Other loans	18,365		13,698
Derivatives, index options	66,738		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	5,511,416		5,931,352
Immediate annuity and supplemental contracts	455,875		422,931
Contingent consideration on businesses acquired	$ 0		4,076
Restatement Adjustment
LIABILITIES
Increase in future policy benefits liability			$ 15,000

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