Investments - Commercial Loan Participations, Past Due (Details) - Commercial mortgage participations $ in Thousands	Sep. 30, 2020 USD ($) loan	Dec. 31, 2019 loan
Financing Receivable, Past Due [Line Items]
Loans past due | $	$ 3,524
Loans past due, number of contracts | loan	1	0
30-59 Days Delinquent
Financing Receivable, Past Due [Line Items]
Loans past due | $	$ 0
Loans past due, number of contracts | loan	0
60-89 days Delinquent
Financing Receivable, Past Due [Line Items]
Loans past due | $	$ 0
Loans past due, number of contracts | loan	0
Greater than 90 Days Delinquent
Financing Receivable, Past Due [Line Items]
Loans past due | $	$ 3,524
Loans past due, number of contracts | loan	1