Consolidated Statements of Operations (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenues
Net earned premiums	$ 1,035,467us-gaap_PremiumsEarnedNet	$ 1,001,631us-gaap_PremiumsEarnedNet	$ 1,007,986us-gaap_PremiumsEarnedNet
Net investment income	180,734us-gaap_NetInvestmentIncome	182,960us-gaap_NetInvestmentIncome	198,728us-gaap_NetInvestmentIncome
Net realized gains on investments, excluding other-than-temporary investment losses	16,365	13,489	10,026
Total other-than-temporary investment losses	(55)us-gaap_ImpairmentOfInvestments	(1,969)us-gaap_ImpairmentOfInvestments	(53)us-gaap_ImpairmentOfInvestments
Portion of net loss recognized in other comprehensive income, before taxes	31	104	0
Net other-than-temporary investment losses recognized in earnings	(24)	(1,865)	(53)
Amortization of deferred gains on disposal of businesses	(5,147)	11,216	12,506
Fees and other income	11,934us-gaap_OtherIncome	8,877us-gaap_OtherIncome	8,416us-gaap_OtherIncome
Total revenues	1,239,329us-gaap_Revenues	1,216,308us-gaap_Revenues	1,237,609us-gaap_Revenues
Benefits, losses and expenses
Policyholder benefits	746,101	745,247	731,862
Amortization of deferred acquisition costs and value of business acquired	32,638	29,988	28,758
Underwriting, general and administrative expenses	356,413	348,232	346,292
Total benefits, losses and expenses	1,135,152us-gaap_BenefitsLossesAndExpenses	1,123,467us-gaap_BenefitsLossesAndExpenses	1,106,912us-gaap_BenefitsLossesAndExpenses
Income before provision for income taxes	104,177	92,841	130,697
Provision for income taxes	34,999us-gaap_IncomeTaxExpenseBenefit	30,077us-gaap_IncomeTaxExpenseBenefit	41,292us-gaap_IncomeTaxExpenseBenefit
Net income	$ 69,178us-gaap_NetIncomeLoss	$ 62,764us-gaap_NetIncomeLoss	$ 89,405us-gaap_NetIncomeLoss

The total amount of expense recognized during the period for future policy benefits, claims and claims adjustment costs, and for selling, general and administrative costs.

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This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting.

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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Reflects the sum of all other revenue and income recognized by the entity in the period not otherwise specified in the income statement.

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Amount before tax of other than temporary impairment (OTTI) on investment in available-for-sale debt security, recognized in other comprehensive loss, attributable to parent entity.

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The amount of other than temporary impairment losses on investments in debt and equity securities categorized as Available-for-sale which have been recognized in earnings during the period. Such impairment losses consist of other than temporary impairments (OTTI) on equity securities, credit losses on investments in debt securities, and when the entity intends to sell an impaired debt security or it is more likely than not that the entity will be required to sell the impaired debt security before recovery of its amortized cost basis.

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Amount, after effects of policies assumed or ceded, of expense related to the provision for policy benefits and costs incurred.

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Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums earned.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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Represents the total amortization expense with respect to capitalized deferred acquisition cost (""DAC"") and value of business acquired (""VOBA"") reflected in the results of operation for the period. DAC typically includes the nature of costs incurred in an acquisition, which primarily consists of commission, policy issuance costs and certain direct marketing expenses. VOBA represents the Company's present value of future profits embedded in acquired businesses (i.e. business combinations or assumption reinsurance).

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