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v3.3.1.900

Investments (Narrative) (Details) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2015 USD ($) Affiliate investment_interest Issuer Security | Dec. 31, 2014 USD ($) Issuer Security | Dec. 31, 2013 USD ($) | Dec. 31, 2012 USD ($)
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Number of investment affiliates exceeding shareholder's equity ten percent threshold limit | Affiliate | 0 |  |  |
Threshold limit of investments based on shareholders' equity | 10.00% |  |  |
Securities on deposit with state insurance departments | $ 48,800 |  |  |
Business owned life insurance cost | 33,000 |  |  |
Investment in unconsolidated subsidiaries | 311,908 | $ 276,501 |  |
Investments in limited liability companies and limited partnerships fair value | 162,624 | 133,250 |  |
Estimated fair value of interest | 19,400 | 10,100 |  |
Equity in earnings (loss) from unconsolidated subsidiaries | 10,100 | 10,700 | $ 10,100 |
Tax credits related to qualified affordable housing investments | 18,400 | 17,900 | 17,900 |
Effect of conversion to equity method, total |  |  | 10,500 |
Effect of conversion to equity method, prior years |  |  | 8,400 |
Net impairments recognized in earnings | 15,345 | 1,207 | 71 |
Credit-related OTTI | 5,751 | $ 232 | $ 83 | $ 3,301
OTTI cost-method investment | $ 8,100 |  |  |
Tax Credit Partnerships Almost 100% Ownership [Member] |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Number of tax credit partnerships almost 100% ownership percentage | investment_interest | 2 |  |  |
Investment in unconsolidated subsidiaries | $ 53,400 |  |  |
Tax Credit Partnerships Less Than 20% Ownership [Member] |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Investment in unconsolidated subsidiaries | $ 68,100 |  |  |
Other Limited Partnerships and Limited Liability Company, Greater Than 25% Ownership [Member] |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Percentage ownership (greater than) | 25.00% |  |  |
Investment in unconsolidated subsidiaries | $ 8,300 |  |  |
Other Limited Partnerships and Limited Liability Company Less than 25% Ownership [Member] |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Percentage ownership (greater than) | 25.00% |  |  |
Investment in unconsolidated subsidiaries | $ 173,700 |  |  |
Maximum [Member] |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Period for federal home loan bank stock liquidation process | 5 years |  |  |
Maximum [Member] | Tax Credit Partnerships Almost 100% Ownership [Member] |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Percentage ownership (greater than) | 100.00% |  |  |
Maximum [Member] | Tax Credit Partnerships Less Than 20% Ownership [Member] |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Percentage ownership (greater than) | 20.00% |  |  |
Debt Securities [Member] |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
FAL Deposit assets | $ 95,400 |  |  |
Short-term Investments [Member] |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
FAL Deposit assets | $ 400 |  |  |
Non Government-Backed [Member] |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Number of debt securities in unrealized loss position | Security | 773 | 588 |  |
Debt securities in unrealized loss position as percentage of total debt securities held | 28.80% | 20.50% |  |
Number of issuers in unrealized loss position | Issuer | 506 | 434 |  |
Single greatest unrealized loss position | $ 1,400 | $ 1,700 |  |
Second greatest unrealized loss position | 1,300 | $ 700 |  |
Corporate Bonds [Member] |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Net impairments recognized in earnings | 7,200 |  |  |
Credit-related OTTI | $ 4,900 |  |  |
Debt Securities, Number of Issuers | Issuer | 6 |  |  |
Non-credit impairment | $ 3,700 |  |  |
Revolving Credit Facility [Member] |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Available-for-sale securities pledged as collateral | $ 125,600 |  |  |

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