Investments (Net Impairment Losses) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013 securities	Dec. 31, 2012
Schedule of Cost-method Investments [Line Items]
Total other-than-temporary impairment recoveries (losses) on debt securities	$ 125	$ 909	$ 1,121
Portion recognized in comprehensive income	(132)	(1,151)	(2,364)
Net impairment losses (gains) on debt securities recognized in earnings	(7)	(242)	(1,243)
Equity securities impairments	(143)	(63)	(98)
Net OTTI losses recognized in earnings	$ (150)	$ (305)	$ (1,341)
Number of debt securities		1

Other than Temporary Impairment Losses, Investments, Equity Securities

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Other than Temporary Impairment Losses, Investments, Number of Debt 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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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 35

-Paragraph 34D

-URI http://asc.fasb.org/extlink&oid=27723805&loc=SL6284304-111560

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-Name Accounting Standards Codification

-Topic 220

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-Section 45

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

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