Fair Value of Assets and Liabilities (Quantitative Info for Level 3 Inputs) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Corporate securities	$ 225,363	$ 323,289
Policyholders’ account balances	11,663,141	11,749,651
Fair Value, Measurements, Recurring
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Future policy benefits	3,392,954	4,060,214
Policyholders’ account balances	$ 1,933,466	2,040,532
Level 3 | Minimum
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Policyholder Age	45 years
Level 3 | Minimum     | Future policy benefits
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Mortality rate	0.00%
Level 3 | Maximum
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Policyholder Age	90 years
Level 3 | Fair Value, Measurements, Recurring
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Future policy benefits	$ 3,392,954	4,060,214
Policyholders’ account balances	$ 1,933,466	$ 2,040,532
Level 3 | Internal | Minimum     | Discounted cash flow | Future policy benefits
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Lapse rate	1.00%	1.00%
Spread over LIBOR	0.20%	0.03%
Utilization rate	39.00%	39.00%
Withdrawal rate (greater than maximum range)	76.00%	76.00%
Mortality rate	0.00%	0.00%
Equity volatility curve	18.00%	16.00%
Level 3 | Internal | Minimum     | Discounted cash flow | Policyholders' account balances
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Lapse rate	1.00%	1.00%
Spread over LIBOR	0.20%	0.03%
Equity volatility curve	6.00%	6.00%
Level 3 | Internal | Minimum     | Discounted cash flow | Corporate securities
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Discount rate	3.05%	2.34%
Level 3 | Internal | Minimum     | Market comparables | Corporate securities
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
EBITDA multiples	6.5	6.5
Level 3 | Internal | Minimum     | Cost approach | Corporate securities
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Liquidation value	62.58%	62.58%
Level 3 | Internal | Maximum     | Discounted cash flow | Future policy benefits
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Lapse rate	20.00%	20.00%
Spread over LIBOR	1.52%	1.13%
Utilization rate	96.00%	96.00%
Withdrawal rate (greater than maximum range)	100.00%	100.00%
Mortality rate	15.00%	15.00%
Equity volatility curve	26.00%	25.00%
Level 3 | Internal | Maximum     | Discounted cash flow | Policyholders' account balances
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Lapse rate	42.00%	42.00%
Spread over LIBOR	1.52%	1.13%
Equity volatility curve	33.00%	31.00%
Level 3 | Internal | Maximum     | Discounted cash flow | Corporate securities
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Discount rate	20.00%	10.17%
Level 3 | Internal | Maximum     | Market comparables | Corporate securities
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
EBITDA multiples	12.4	12.4
Level 3 | Internal | Maximum     | Cost approach | Corporate securities
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Liquidation value	62.58%	62.58%
Level 3 | Internal | Weighted Average | Discounted cash flow | Corporate securities
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Discount rate	3.79%	2.82%
Level 3 | Internal | Weighted Average | Market comparables | Corporate securities
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
EBITDA multiples	9.2	8.8
Level 3 | Internal | Weighted Average | Cost approach | Corporate securities
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Liquidation value	62.58%	62.58%
Level 3 | Internal | Fair Value, Measurements, Recurring | Future policy benefits
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Future policy benefits	$ 3,392,954	$ 4,060,214
Level 3 | Internal | Fair Value, Measurements, Recurring | Policyholders' account balances
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Policyholders’ account balances	1,933,466	2,040,532
Level 3 | Internal | Fair Value, Measurements, Recurring | Corporate securities
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Corporate securities	154,669	163,312
Level 3 | Internal | Fair Value, Measurements, Recurring | Other assets
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Other assets	376,898	400,441
Level 3 | Internal | Fair Value, Measurements, Recurring | Reinsurance recoverables
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Reinsurance recoverables	$ 1,866,253	$ 1,881,030