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Investments (Other Investment Portfolio by Strategy and the Remaining Commitment Amount Associated With Each Strategy) (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Carrying Value |  | $ 216,807 | $ 178,938
Other Securities [Member] |  |  |
Carrying Value | [1] | 32,667 | 25,042
Remaining Commitment | [1] | 0 | 0
Maximum Exposure to Loss | [1] | 32,667 | 25,042
Real Assets [Member] |  |  |
Carrying Value |  | 23,256 | 27,862
Remaining Commitment |  | 20,741 | 27,129
Maximum Exposure to Loss |  | 43,997 | 54,991
Private Credit Funds [Member] |  |  |
Carrying Value |  | 42,532 | 41,682
Remaining Commitment |  | 105,340 | 81,453
Maximum Exposure to Loss |  | 147,872 | 123,135
Private Equity [Member] |  |  |
Carrying Value |  | 118,352 | 84,352
Remaining Commitment |  | 93,138 | 93,688
Maximum Exposure to Loss |  | 211,490 | 178,040
Other Investment Portfolio [Member] |  |  |
Carrying Value |  | 216,807 | 178,938
Remaining Commitment |  | 219,219 | 202,270
Maximum Exposure to Loss |  | 436,026 | 381,208
Alternative Investments [Member] |  |  |
Carrying Value |  | 184,140 | 153,896
Remaining Commitment |  | 219,219 | 202,270
Maximum Exposure to Loss |  | $ 403,359 | $ 356,166
[1] | Other securities primarily consists of tax credit investments.

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