Investments (Commercial Mortgage and Other Loans) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Commercial Mortgage and Other Loans [Line Items]
Commercial mortgage and agricultural property loans by property type	$ 1,202,191	$ 1,241,653
Commercial mortgage loans, Percentage	100.00%	100.00%
Allowance for Credit Losses	$ (4,559)	$ (1,768)
Total net other loans	927	0
Other loans	927	0
Allowance for credit losses, other loans	0	0
Total commercial mortgage and other loans	1,198,559	1,239,885
Commercial Mortgage and Agricultural Loans
Commercial Mortgage and Other Loans [Line Items]
Total net other loans	1,197,632	1,239,885
Other collateralized loans
Commercial Mortgage and Other Loans [Line Items]
Other loans	927	0
Apartments and multi-family
Commercial Mortgage and Other Loans [Line Items]
Commercial mortgage and agricultural property loans by property type	$ 356,713	$ 355,175
Commercial mortgage loans, Percentage	29.70%	28.60%
Hospitality
Commercial Mortgage and Other Loans [Line Items]
Commercial mortgage and agricultural property loans by property type	$ 33,673	$ 31,449
Commercial mortgage loans, Percentage	2.80%	2.50%
Industrial
Commercial Mortgage and Other Loans [Line Items]
Commercial mortgage and agricultural property loans by property type	$ 310,332	$ 299,803
Commercial mortgage loans, Percentage	25.80%	24.10%
Office
Commercial Mortgage and Other Loans [Line Items]
Commercial mortgage and agricultural property loans by property type	$ 189,770	$ 205,498
Commercial mortgage loans, Percentage	15.80%	16.60%
Other
Commercial Mortgage and Other Loans [Line Items]
Commercial mortgage and agricultural property loans by property type	$ 139,624	$ 136,841
Commercial mortgage loans, Percentage	11.60%	11.00%
Retail
Commercial Mortgage and Other Loans [Line Items]
Commercial mortgage and agricultural property loans by property type	$ 151,200	$ 190,690
Commercial mortgage loans, Percentage	12.60%	15.40%
Commercial mortgage loans
Commercial Mortgage and Other Loans [Line Items]
Commercial mortgage and agricultural property loans by property type	$ 1,181,312	$ 1,219,456
Commercial mortgage loans, Percentage	98.30%	98.20%
Agricultural property loans
Commercial Mortgage and Other Loans [Line Items]
Commercial mortgage and agricultural property loans by property type	$ 20,879	$ 22,197
Commercial mortgage loans, Percentage	1.70%	1.80%

Commercial mortgage loans, Percentage

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Commercial mortgage and agricultural property loans by property type

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Commercial mortgage and other loans

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