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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, 2016 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 03, 2015
Condensed Financial Statements, Captions [Line Items] |  |  |  |  |  |  |  |  |
Proceeds from special purpose investment vehicles |  |  |  |  |  | $ 4,900,000 | $ 8,900,000 |  |
Proceeds from dividends received |  |  |  |  |  | 111,000,000 | 133,000,000 | $ 225,000,000 |
Capital contributions to subsidiaries |  |  |  |  |  | 30,125,000 | 90,125,000 | $ 30,125,000 |
Escrow deposit recovery |  |  |  |  |  | 2,000,000 |  |  |
Loan maximum borrowing capacity |  |  |  |  | $ 250,000,000 |  |  |  |
Revolving credit facility term |  |  |  |  | 5 years |  |  |  |
Credit facility |  |  |  |  |  | 180,000,000 |  |  |
Revolving Credit Facility [Member] |  |  |  |  |  |  |  |  |
Condensed Financial Statements, Captions [Line Items] |  |  |  |  |  |  |  |  |
Loan maximum borrowing capacity |  |  |  |  | $ 200,000,000 |  | 250,000,000 |  | $ 250,000,000
Revolving credit facility term |  |  |  |  | 5 years |  |  |  |
Credit facility |  |  |  |  |  | $ 180,000,000 |  |  |
Interest rate at period end |  |  |  |  |  | 1.73% |  |  |
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 |  |  |  |  |  | 175,000,000 |  |  |
Total borrowing guaranteed |  |  |  |  |  | 140,000,000 |  |  |
Swap [Member] | FFL [Member] |  |  |  |  |  |  |  |  |
Condensed Financial Statements, Captions [Line Items] |  |  |  |  |  |  |  |  |
Swap agreement collateral |  |  |  |  |  | 30,000,000 |  |  |
Notional amount |  |  |  |  |  | $ 108,000,000 | $ 95,000,000 |  |
Term of swap agreement |  |  | 1 year |  |  | 1 year | 1 year |  |
Swap [Member] | FFL [Member] | LIBOR [Member] |  |  |  |  |  |  |  |  |
Condensed Financial Statements, Captions [Line Items] |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  | 1.45% | 1.45% |  | 1.45% | 1.45% |  |
Swap [Member] | AFL [Member] |  |  |  |  |  |  |  |  |
Condensed Financial Statements, Captions [Line Items] |  |  |  |  |  |  |  |  |
Swap agreement collateral |  |  |  |  |  | $ 40,000,000 |  |  |
Notional amount |  |  |  |  |  | $ 152,000,000 | $ 124,000,000 |  |
Term of swap agreement |  |  |  | 3 years |  | 1 year |  |  |
Swap [Member] | AFL [Member] | LIBOR [Member] |  |  |  |  |  |  |  |  |
Condensed Financial Statements, Captions [Line Items] |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  | 1.35% | 1.35% |  | 1.35% | 1.35% |  |

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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Definition Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition The percentage points added to the reference rate to compute the variable rate on the interest rate derivative. + References No definition available. + Details
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- Definition Amount of right to receive securities collateral under master netting arrangements that have not been offset against derivative liabilities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226016-175313 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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- Definition Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition The net cash inflow or outflow for the increase (decrease) associated with funds that are not available for withdrawal or use (such as funds held in escrow) and are associated with underlying transactions that are classified as investing activities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3179-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 + Details
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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 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 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 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 + Details
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- Definition The effective interest rate at the end of the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Bonds or similar securities issued by state, city, or local governments or the agencies operated by state, city, or local governments which are short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash Equivalents -URI http://asc.fasb.org/extlink&oid=6507016 + Details
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- Definition The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585 + Details
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- Definition Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower. + 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 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: 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(a)(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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