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v3.8.0.1

General (Details) $ in Thousands | 1 Months Ended | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
Aug. 31, 2017 USD ($) a | Sep. 30, 2017 USD ($) shares | Sep. 30, 2016 USD ($) shares | Sep. 30, 2017 USD ($) shares | Sep. 30, 2016 USD ($) shares
Organization, Consolidation and Presentation of Financial Statements [Abstract] |  |  |  |  |
Potentially dilutive securities (in shares) | shares |  | 0 | 22,000 | 0 | 29,000
Deferred policy acquisition cost amortization |  | $ 136,290 | $ 140,203 | $ 416,728 | $ 421,685
Advertising expenses |  |  |  | 32,000 | 34,100
Property, Plant and Equipment [Line Items] |  |  |  |  |
Sale of land, gain |  |  |  | $ 3,307 | $ 0
Brea, California [Member] |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Area of land (in acres) | a | 6 |  |  |  |
Sale of land, sales price | $ 12,200 |  |  |  |
Sale of land, Promissory note receivable | 5,700 |  |  |  |
Sale of land, gain | $ 3,300 |  |  |  |
Brea, California [Member] | Note Receivable [Member] |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Interest rate | 3.50% |  |  |  |

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