Investments (Net Realized Investment Gains (Losses)) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Total other-than-temporary impairment losses:
Other-than-temporary impairment (OTTI) losses	$ (19,917)	$ (1,475)	$ (71)
Portion of OTTI losses recognized in other comprehensive income before taxes	4,572	268	0
Net impairments recognized in earnings	(15,345)	(1,207)	(71)
Gross realized gains, available-for-sale securities	11,936	5,627	18,130
Gross realized (losses), available-for-sale securities	(11,481)	(1,103)	(7,031)
Net realized gains (losses), trading securities	1,080	28,018	20,444
Net realized gains (losses), Other investments	464	326	0
Change in unrealized holding gains (losses), trading securities	(28,343)	(18,883)	35,507
Change in unrealized holding gains (losses), convertible securities, carried at fair value	(896)	1,876	0
Other	946	0	925
Total net realized investment gains (losses)	(41,639)	14,654	67,904
State and municipal bonds [Member]
Total other-than-temporary impairment losses:
Other-than-temporary impairment (OTTI) losses	0	(50)	(71)
Corporate debt [Member]
Total other-than-temporary impairment losses:
Other-than-temporary impairment (OTTI) losses	(11,781)	(1,425)	0
Other Investments [Member]
Total other-than-temporary impairment losses:
Other-than-temporary impairment (OTTI) losses	$ (8,136)	$ 0	$ 0

This item represents the gain (loss) realized during the period from the sale of Other Investments.

No definition available.

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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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 and losses recognized for other than temporary impairments (OTTI) of the subject investments.

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-Publisher FASB
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The difference between the book value and the sale price of other nonspecific investments. This element is used when other, more specific, elements are not appropriate. This element refers to the gain (loss) included in earnings.

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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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Amount before tax of other than temporary impairment loss (OTTI) on investments in available-for-sale and held-to-maturity debt securities, recognized in other comprehensive loss and attributable to parent entity.

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The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

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Amount of gain (loss) realized from securities classified as trading.

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Amount of unrealized holding gain (loss) recognized in the income statement for investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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Amount of the unrealized gain (loss) in earnings for the period from the increase (decrease) in fair value on hybrid instruments measured at fair value.

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