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Condensed Financial Information of Registrant Condensed Financial Information of Registrant (Narratives) (Details) - USD ($) |  |  |  |  |  | 12 Months Ended |
--- | --- | --- | --- | --- | --- | --- | ---
Jan. 12, 2015 | Jan. 02, 2015 | Feb. 13, 2014 | Aug. 09, 2013 | Jul. 02, 2013 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 03, 2014
Condensed Financial Statements, Captions [Line Items] |  |  |  |  |  |  |  |  |  |
Proceeds from special purpose investment vehicles |  |  |  |  |  |  | $ 8,900,000 | $ 6,800,000 |  |
Proceeds from dividends received |  |  |  |  |  |  | 133,000,000 | 225,000,000 | $ 120,000,000 |
Capital contributions to subsidiaries |  |  |  |  |  |  | 90,125,000 | 30,125,000 | $ 40,125,000 |
Loan maximum borrowing capacity |  |  |  |  |  | $ 200,000,000 |  |  |  |
Revolving credit facility term |  |  |  |  |  | 5 years |  |  |  |
Credit facility | [1] |  |  |  |  |  | 150,000,000 | 150,000,000 |  |
Total borrowing guaranteed |  |  |  |  |  |  | 20,000,000 | $ 20,000,000 |  |
Revolving Credit Facility [Member] |  |  |  |  |  |  |  |  |  |
Condensed Financial Statements, Captions [Line Items] |  |  |  |  |  |  |  |  |  |
Loan maximum borrowing capacity |  |  |  |  |  | $ 200,000,000 |  |  |  | $ 250,000,000
Revolving credit facility term |  |  |  |  |  | 5 years |  |  |  |
Credit facility |  |  |  |  |  |  | $ 150,000,000 |  |  |
Interest rate at period end |  |  |  |  |  |  | 1.53% |  |  |
Workmen's Auto Insurance Company [Member] |  |  |  |  |  |  |  |  |  |
Condensed Financial Statements, Captions [Line Items] |  |  |  |  |  |  |  |  |  |
Consideration paid in cash |  |  | $ 8,000,000 |  |  |  |  |  |  |
Amount held in escrow |  |  | $ 2,000,000 |  |  |  |  |  |  |
Term for escrow security payment |  |  | 3 years |  |  |  |  |  |  |
Capital contribution amount |  | $ 15,000,000 |  |  |  |  |  |  |  |
Mcc [Member] |  |  |  |  |  |  |  |  |  |
Condensed Financial Statements, Captions [Line Items] |  |  |  |  |  |  |  |  |  |
Credit facility |  |  |  |  |  |  | $ 120,000,000 |  |  |
Bank loan |  |  |  |  |  |  | 20,000,000 |  |  |
Municipal bonds, fair value |  |  |  |  |  |  | 180,000,000 |  |  |
Total borrowing guaranteed |  |  |  |  |  |  | 140,000,000 |  |  |
Swap [Member] | FFL [Member] |  |  |  |  |  |  |  |  |  |
Condensed Financial Statements, Captions [Line Items] |  |  |  |  |  |  |  |  |  |
Notional amount |  |  |  |  |  |  | 95,000,000 |  |  |
Swap agreement collateral |  |  |  |  |  |  | 30,000,000 |  |  |
Term of swap agreement |  |  |  | 1 year | 3 years |  |  |  |  |
Swap [Member] | FFL [Member] | LIBOR [Member] |  |  |  |  |  |  |  |  |  |
Condensed Financial Statements, Captions [Line Items] |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  | 1.40% | 140000.00% |  |  |  |  |
Swap [Member] | AFL [Member] |  |  |  |  |  |  |  |  |  |
Condensed Financial Statements, Captions [Line Items] |  |  |  |  |  |  |  |  |  |
Notional amount |  |  |  |  |  |  | 124,000,000 |  |  |
Swap agreement collateral |  |  |  |  |  |  | $ 40,000,000 |  |  |
Swap [Member] | AFL [Member] | LIBOR [Member] |  |  |  |  |  |  |  |  |  |
Condensed Financial Statements, Captions [Line Items] |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  | 120000.00% | 1.20% |  |  |  |  |
[1] | On July 2, 2013, the Company entered into an unsecured $200 million five-year revolving credit facility. The interest rate on borrowings under the credit facility is based on the Company's debt to total capital ratio and ranges from LIBOR plus 112.5 basis points when the ratio is under 15% to LIBOR plus 162.5 basis points when the ratio is above 25%. Commitment fees for the undrawn portions of the credit facility range from 12.5 basis points when the ratio is under 15% to 22.5 basis points when the ratio is above 25%. Debt to capital ratio is expressed as a percentage of (i) consolidated debt to (ii) consolidated shareholders' equity plus consolidated debt. Effective December 3, 2014, the Company extended the maturity date of the unsecured credit facility from June 30, 2018 to December 3, 2019, and expanded the borrowing capacity from $200 million to $250 million. In 2015 and 2014, the interest rate was LIBOR plus 112.5 basis points on the $150 million of borrowings and 12.5 basis points on the undrawn portion of the credit facility. The interest rate was approximately 1.53% at December 31, 2015.

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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 20, 22 -Article 5 + Details
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