Investments (Commercial Mortgage and Other Loans) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Commercial Mortgage and Other Loans [Line Items]
Commercial mortgage and agricultural property loans by property type	$ 1,241,653	$ 1,211,215
Commercial mortgage loans, Percentage	100.00%	100.00%
Allowance for Credit Losses	$ (1,768)	$ (2,065)
Financing Receivable, after Allowance for Credit Loss	1,239,885	1,209,150
Total Commercial mortgage and other loans		1,209,150
Apartments/Multi-Family
Commercial Mortgage and Other Loans [Line Items]
Commercial mortgage and agricultural property loans by property type	$ 355,175	$ 362,811
Commercial mortgage loans, Percentage	28.60%	29.90%
Hospitality
Commercial Mortgage and Other Loans [Line Items]
Commercial mortgage and agricultural property loans by property type	$ 31,449	$ 16,083
Commercial mortgage loans, Percentage	2.50%	1.30%
Industrial
Commercial Mortgage and Other Loans [Line Items]
Commercial mortgage and agricultural property loans by property type	$ 299,803	$ 263,999
Commercial mortgage loans, Percentage	24.10%	21.80%
Office
Commercial Mortgage and Other Loans [Line Items]
Commercial mortgage and agricultural property loans by property type	$ 205,498	$ 187,450
Commercial mortgage loans, Percentage	16.60%	15.50%
Other
Commercial Mortgage and Other Loans [Line Items]
Commercial mortgage and agricultural property loans by property type	$ 136,841	$ 131,961
Commercial mortgage loans, Percentage	11.00%	10.90%
Retail
Commercial Mortgage and Other Loans [Line Items]
Commercial mortgage and agricultural property loans by property type	$ 190,690	$ 193,473
Commercial mortgage loans, Percentage	15.40%	16.00%
Commercial mortgage loans
Commercial Mortgage and Other Loans [Line Items]
Commercial mortgage and agricultural property loans by property type	$ 1,219,456	$ 1,155,777
Commercial mortgage loans, Percentage	98.20%	95.40%
Agricultural property loans
Commercial Mortgage and Other Loans [Line Items]
Commercial mortgage and agricultural property loans by property type	$ 22,197	$ 55,438
Commercial mortgage loans, Percentage	1.80%	4.60%

Commercial mortgage loans, Percentage

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- Definition

Commercial mortgage and agricultural property loans by property type

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- Definition

Commercial mortgage and other loans

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- Definition

The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118959141&loc=d3e21338-158488

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Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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