Reinsurance - Reinsurance Recoverables and Financial Strength Ratings by Reinsurer (Details) - USD ($) $ in Thousands		Sep. 30, 2020	Dec. 31, 2019
Ceded Credit Risk [Line Items]
Reinsurance recoverables		$ 4,229,088	$ 4,169,823
Pecan Re Inc [Member] | External credit rating, not rated [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverables	[1],[2]	2,670,796	2,696,924
SCOR Global Life Reinsurance Companies [Member] | AM Best, A+ Rating [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverables	[3]	377,723	352,049
Munich Re of Malta [Member] | External credit rating, not rated [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverables	[2],[4]	272,995	286,433
Swiss Re Life & Health America Inc. [Member] | AM Best, A+ Rating [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverables	[5]	238,367	233,572
American Health and Life Insurance Company [Member] | AM Best, B++ Rating [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverables	[2]	164,540	167,471
Munich American Reassurance Company [Member] | AM Best, A+ Rating [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverables		131,762	118,372
Korean Reinsurance Company [Member] | AM Best, A Rating [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverables		118,640	108,410
RGA Reinsurance [Member] | AM Best, A+ Rating [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverables		118,766	100,328
Hannover Life Reassurance Company [Member] | AM Best, A+ Rating [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverables		39,820	33,772
TOA Reinsurance Company [Member] | AM Best, A Rating [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverables		37,053	26,160
All Other Reinsurers [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverables		64,220	48,679
Allowance for Credit Losses [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverables		$ (5,594)	$ (2,347)

[1] Pecan Re Inc. is a wholly owned subsidiary of Swiss Re Life & Health America Inc.

[2] Reinsurance recoverables includes balances ceded under coinsurance transactions of term life insurance policies that were in force as of December 31, 2009. Amounts shown are net of their share of the reinsurance recoverables from other reinsurers.  Arrangements with these reinsurers include collateral trust agreements held in support of reinsurance recoverables.

[3] Includes amounts ceded to Transamerica Reinsurance Companies and fully retroceded to SCOR Global Life Reinsurance Companies.

[4] Entity is rated AA- by S&P.

[5] Includes amounts ceded to Lincoln National Life Insurance and fully retroceded to Swiss Re Life & Health America Inc.