Collateral Finance and Securitization Notes (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jun. 30, 2006
Collateral Finance Facility [Line Items]
Debt Instrument, Face Amount				$ 850,000,000.0
Direct investment in subsidiary				$ 112,800,000
Assets Held-in-trust	$ 767,900,000	$ 841,500,000
Amount Held In Debt Service Coverage Account	57,100,000	39,700,000
Collateral Financing Expense	29,699,000	28,636,000	$ 25,827,000
Debt Issuance Cost	18,651,000	20,405,000
Reinsurance Group Of America Barbados [Member]
Collateral Finance Facility [Line Items]
Collateral Financing Expense	$ 5,100,000	4,200,000	4,000,000
Timerberlake Financial [Member]
Collateral Finance Facility [Line Items]
Debt Instrument, Issuance Date	Jun. 01, 2006
Collateral Financing Expense	$ 9,400,000	6,400,000	4,200,000
Chesterfield Financial Holdings LLC [Member]
Collateral Finance Facility [Line Items]
Debt Instrument, Face Amount	300,000,000.0
Assets Held-in-trust	13,500,000	19,400,000
Collateral Financing Expense	$ 9,500,000	$ 11,300,000	$ 13,100,000
Debt Instrument, Interest Rate, Stated Percentage	4.50%
Minimum [Member]
Collateral Finance Facility [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	$ 35,000,000