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Investments (Narrative) (Details) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2018 USD ($) Business Issuer investment_interest Security | Jun. 30, 2017 USD ($) | Jun. 30, 2018 USD ($) Business Issuer investment_interest Security | Jun. 30, 2017 USD ($) | Dec. 31, 2017 USD ($) Issuer Security
Reclassifications from AOCI to net income: |  |  |  |  |
Number of Investment Affiliates Exceeding Shareholder's Equity Ten Percent Threshold Limit | investment_interest | 0 |  | 0 |  |
Threshold Limit Of Investments Based On Shareholders Equity | 10.00% |  | 10.00% |  |
Securities on deposit with state insurance departments | $ 45,700 |  | $ 45,700 |  |
Business owned life insurance cost | $ 33,000 |  | $ 33,000 |  |
Number of LPs / LLCs with investment ownership percent over 25% | Business | 3 |  | 3 |  |
Investment in unconsolidated subsidiaries | $ 390,214 |  | $ 390,214 |  | $ 330,591
OTTI losses | (404) | $ 0 | (404) | $ (419) |
Net impairment losses recognized in earnings | 404 | 0 | 404 | 171 |
Portion of noncredit OTTI losses recognized in OCI | $ 0 | $ 0 | $ 0 | 248 |
Tax Credit Partnerships Almost 100% Ownership |  |  |  |  |
Reclassifications from AOCI to net income: |  |  |  |  |
Number of tax credit partnerships almost 100% ownership percentage | investment_interest | 2 |  | 2 |  |
Investment in unconsolidated subsidiaries | $ 28,500 |  | $ 28,500 |  | 32,500
Tax Credit Partnerships Less Than 20% Ownership |  |  |  |  |
Reclassifications from AOCI to net income: |  |  |  |  |
Investment in unconsolidated subsidiaries | 46,400 |  | 46,400 |  | 52,100
Other Limited Partnerships and Limited Liability Company, Greater Than 25% Ownership |  |  |  |  |
Reclassifications from AOCI to net income: |  |  |  |  |
Investment in unconsolidated subsidiaries | 28,400 |  | 28,400 |  | 30,800
Other Limited Partnerships and Limited Liability Company Less than 25% Ownership |  |  |  |  |
Reclassifications from AOCI to net income: |  |  |  |  |
Investment in unconsolidated subsidiaries | $ 281,900 |  | $ 281,900 |  | $ 209,100
Maximum | Tax Credit Partnerships Almost 100% Ownership |  |  |  |  |
Reclassifications from AOCI to net income: |  |  |  |  |
Investment ownership percentage | 100.00% |  | 100.00% |  |
Maximum | Tax Credit Partnerships Less Than 20% Ownership |  |  |  |  |
Reclassifications from AOCI to net income: |  |  |  |  |
Investment ownership percentage | 20.00% |  | 20.00% |  |
Fixed maturities |  |  |  |  |
Reclassifications from AOCI to net income: |  |  |  |  |
Required FAL Deposit | $ 123,600 |  | $ 123,600 |  |
Short-term investments |  |  |  |  |
Reclassifications from AOCI to net income: |  |  |  |  |
Required FAL Deposit | $ 1,000 |  | $ 1,000 |  |
Non Government-Backed |  |  |  |  |
Reclassifications from AOCI to net income: |  |  |  |  |
Number of debt securities in unrealized loss position | Security | 1,024 |  | 1,024 |  | 629
Debt securities in unrealized loss position as percentage of total debt securities held | 50.00% |  | 50.00% |  | 26.50%
Number of issuers in unrealized loss position | Issuer | 548 |  | 548 |  | 375
Single greatest unrealized loss position | $ 600 |  | $ 600 |  | $ 400
Second greatest unrealized loss position | $ 400 |  | $ 400 |  | $ 300
Corporate Bond Securities |  |  |  |  |
Reclassifications from AOCI to net income: |  |  |  |  |
Portion of noncredit OTTI losses recognized in OCI |  |  |  | $ 200 |

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