Investments (Investment Gains and Losses) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Held to maturity debt securities:
Real estate gains (losses)	$ 0	$ 89
Totals	978	1,548
Percentage of gains on bonds, due to calls of securities	75.00%
Total other-than-temporary impairment gains (losses) on debt securities	160	(4)
Portion of loss (gain) recognized in comprehensive income	(160)	(3)
Net impairment losses on debt securities recognized in earnings	0	(7)
Equity securities impairments	0	(28)
Net OTTI losses recognized in earnings	0	(35)
Non-Credit Other-than-Temporary Impairment, Credit Losses Recognized in Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance, cumulative credit losses related to other-than-temporary impairments	2,298	2,472	2,472
Reductions for securities sold during current period	(20)		(181)
Additions for credit losses not previously recognized in other-than-temporary impairments	0		7
Ending balance, cumulative credit losses related to other-than-temporary impairments	2,278		2,298
Debt Securities [Member]
Available for sale debt securities:
Realized gains on disposal	213	692
Realized losses on disposal	(9)	(8)
Held to maturity debt securities:
Realized gains on disposal	724	782
Realized losses on disposal	0	(11)
Equity Securities [Member]
Held to maturity debt securities:
Equity securities realized gains (losses)	$ 50	$ 4

Held-to-maturity Securities, Realized Gains on Disposal

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Held-to-maturity Securities, Realized Losses on Disposal

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Investments, Percentage of Gains on Bonds, Due to Calls of Securities

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Other than Temporary Impairment Losses, Investments, Equity Securities

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Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net, Debt Securities

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Total Other-than-temporary Impairment (Losses) Recoveries on Debt Securities

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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.

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The difference between the carrying value and the sale price of equity securities, not separately or otherwise categorized as trading or available-for-sale. This element includes investments in which the entity holds a small ownership stake (generally, less than 20% of the shares outstanding) and cannot exert significant influence.

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The net gain (loss) resulting from sales and other disposals of real estate owned for investment purposes.

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This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which no such other than temporary impairment (OTTI) was previously recognized.

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The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

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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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