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Investments (OTTI) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] |  |  |  |
Current Provision for Securities without Prior Allowance | $ 1,025 |  | $ 8,100 |
Credit Loss, (Expense) Benefit | 2,854 |  | (8,227) |
Other Impairment Expense | (44) |  | (16,259) |
OTTI benefit (expense) recognized in earnings | 2,810 | $ (2,291) | (24,486) | $ (3,366)
Other Investments [Member] |  |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] |  |  |  |
Other Impairment Expense | 0 |  | 0 |
OTTI benefit (expense) recognized in earnings | 0 | (610) | 0 | (846)
Other investments, Credit Loss (Expense) Benefit | 0 |  | 0 |
Short-Term Investments [Member] |  |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] |  |  |  |
Other Impairment Expense | 0 |  | 0 |
OTTI benefit (expense) recognized in earnings | (1) | 0 | (1) | 0
Short term investments, allowance for credit loss | (1) |  | (1) |
Commercial Mortgage Loans [Member] |  |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] |  |  |  |
Other Impairment Expense | 0 |  | 0 |
OTTI benefit (expense) recognized in earnings | (2) | 0 | (220) | 0
CML, Credit Loss (Expense) Benefit | (2) |  | (220) |
Available-for-sale Securities [Member] |  |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] |  |  |  |
Current Provision for Securities without Prior Allowance | 2,854 |  | (8,010) |
Other Impairment Expense | (44) |  | (16,259) |
OTTI benefit (expense) recognized in earnings | 2,810 | (1,681) | (24,269) | (2,520)
Available-for-sale Securities [Member] | U.S. Government and Government Agencies [Member] |  |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] |  |  |  |
Current Provision for Securities without Prior Allowance |  |  | 0 |
Other Impairment Expense |  |  | (14) |
OTTI benefit (expense) recognized in earnings |  |  | (14) | 0
Available-for-sale Securities [Member] | Foreign Government [Member] |  |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] |  |  |  |
Current Provision for Securities without Prior Allowance | 3 |  | (25) |
Other Impairment Expense | 0 |  | 0 |
OTTI benefit (expense) recognized in earnings | 3 | 0 | (25) | 0
Available-for-sale Securities [Member] | Obligations of States and Political Subdivisions [Member] |  |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] |  |  |  |
Current Provision for Securities without Prior Allowance | 2 |  | (15) |
Other Impairment Expense | 0 |  | (62) |
OTTI benefit (expense) recognized in earnings | 2 | 0 | (77) | (65)
Available-for-sale Securities [Member] | Corporate Securities [Member] |  |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] |  |  |  |
Current Provision for Securities without Prior Allowance | 2,454 |  | (6,018) |
Other Impairment Expense | 0 |  | (12,103) |
OTTI benefit (expense) recognized in earnings | 2,454 | (1,681) | (18,121) | (2,455)
Available-for-sale Securities [Member] | Collateralized Loan Obligations and Other Asset Backed Securities [Member] |  |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] |  |  |  |
Current Provision for Securities without Prior Allowance | 217 |  | (1,230) |
Other Impairment Expense | (44) |  | (2,137) |
OTTI benefit (expense) recognized in earnings | 173 | 0 | (3,367) | 0
Available-for-sale Securities [Member] | Residential Mortgage Backed Securities [Member] |  |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] |  |  |  |
Current Provision for Securities without Prior Allowance | 157 |  | (690) |
Other Impairment Expense | 0 |  | (91) |
OTTI benefit (expense) recognized in earnings | 157 | 0 | (781) | 0
Available-for-sale Securities [Member] | Commercial Mortgage Backed Securities [Member] |  |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] |  |  |  |
Current Provision for Securities without Prior Allowance | 21 |  | (32) |
Other Impairment Expense | 0 |  | (1,852) |
OTTI benefit (expense) recognized in earnings | 21 | 0 | (1,884) | 0
Held-to-maturity Securities [Member] |  |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] |  |  |  |
Held to Maturity, Credit Loss (Expense) Benefit | 3 |  | 4 |
Other Impairment Expense | 0 |  | 0 |
OTTI benefit (expense) recognized in earnings | 3 | 0 | 4 | 0
Held-to-maturity Securities [Member] | Corporate Securities [Member] |  |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] |  |  |  |
Held to Maturity, Credit Loss (Expense) Benefit | 3 |  | 4 |
Other Impairment Expense | 0 |  | 0 |
OTTI benefit (expense) recognized in earnings | $ 3 | $ 0 | 4 | $ 0
Other than temporary impairment losses, investments [Member] |  |  |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] |  |  |  |
OTTI benefit (expense) recognized in earnings |  |  | $ (24,500) |

X
- Definition Amount of credit related OTTI on commercial mortgage loans. + References No definition available. + Details
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- Definition The credit loss expensed during the period on investment portfolio. + References No definition available. + Details
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X
- Definition The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting. + References No definition available. + Details
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- Definition Amount of expense for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), for which no credit loss was previously recorded. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 9 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922900-210455 + Details
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- Definition Amount of increase (decrease) in allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447 + Details
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