Summary of Significant Accounting Policies - Narrative - Policyholder Account Balances (Details)	Dec. 31, 2019 Rate
Minimum
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability for Policyholder Contract Deposits, Interest Rate	3.00%
Maximum
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability for Policyholder Contract Deposits, Interest Rate	4.00%

Rate of interest credited to policyholder deposits.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6482852&loc=d3e14931-158439

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.13(b))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Name:	us-gaap_LiabilityForPolicyholderContractDepositsInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant