Securities in an Unrealized Loss Position (Non-Investment Grade Fixed Maturity Securities) (Details) - External Credit Rating, Non Investment Grade $ in Thousands	Dec. 31, 2019 USD ($)
Foreign government
Debt Securities, Available-for-sale [Line Items]
Number of Securities	21
Aggregate Fair Value	$ 79,747
Gross Unrealized Loss	$ 92,369
Total corporate
Debt Securities, Available-for-sale [Line Items]
Number of Securities	14
Aggregate Fair Value	$ 65,710
Gross Unrealized Loss	$ 4,319
Mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Number of Securities	5
Aggregate Fair Value	$ 954
Gross Unrealized Loss	$ 17
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Number of Securities	5
Aggregate Fair Value	$ 437
Gross Unrealized Loss	$ 113
Debt Securities
Debt Securities, Available-for-sale [Line Items]
Number of Securities	45
Aggregate Fair Value	$ 146,848
Gross Unrealized Loss	$ 96,818