Investments (Held-To-Maturity Securities Disclosure) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Amortized Cost	$ 317,179	$ 390,622
Net Unrealized Gains (Losses)	958	2,257
Total HTM fixed income securities carrying value	318,137us-gaap_HeldToMaturitySecurities	392,879us-gaap_HeldToMaturitySecurities
Unrecognized Holding Gains	15,824	24,102
Unrecognized Holding Losses	0	0
Total HTM fixed income securities fair value	333,961	416,981
Held To Maturity Securities Average Duration	1 year 8 months 8 days
Foreign Government [Member]
Amortized Cost	5,292	5,292
Net Unrealized Gains (Losses)	47	131
Total HTM fixed income securities carrying value	5,339	5,423
Unrecognized Holding Gains	55	168
Unrecognized Holding Losses	0	0
Total HTM fixed income securities fair value	5,394	5,591
Obligations of States and Political Subdivisions [Member]
Amortized Cost	285,301	348,109
Net Unrealized Gains (Losses)	2,071	4,013
Total HTM fixed income securities carrying value	287,372	352,122
Unrecognized Holding Gains	11,760	17,634
Unrecognized Holding Losses	0	0
Total HTM fixed income securities fair value	299,132	369,756
Corporate Securities [Member]
Amortized Cost	18,899	28,174
Net Unrealized Gains (Losses)	(273)	(346)
Total HTM fixed income securities carrying value	18,626	27,828
Unrecognized Holding Gains	2,796	2,446
Unrecognized Holding Losses	0	0
Total HTM fixed income securities fair value	21,422	30,274
Asset-backed Securities [Member]
Amortized Cost	2,818	3,413
Net Unrealized Gains (Losses)	(455)	(655)
Total HTM fixed income securities carrying value	2,363	2,758
Unrecognized Holding Gains	460	657
Unrecognized Holding Losses	0	0
Total HTM fixed income securities fair value	2,823	3,415
Commercial Mortgage Backed Securities [Member]
Amortized Cost	4,869	5,634
Net Unrealized Gains (Losses)	(432)	(886)
Total HTM fixed income securities carrying value	4,437	4,748
Unrecognized Holding Gains	753	3,197
Unrecognized Holding Losses	0	0
Total HTM fixed income securities fair value	$ 5,190	$ 7,945

Held to maturity securities average duration.

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The remaining aggregate increase (decrease) in the market value of held-to-maturity securities either (i) prior to the securities' transfer to a held-to-maturity designation or (ii) resulting from a non-credit other-than-temporary impairment.

+ References

No definition available.

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

+ References

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

-Publisher FASB

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Amount of accumulated unrealized gain on investments in debt securities classified as held-to-maturity.

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Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity.

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Amount before other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Fair value of investments in debt securities classified as held-to-maturity.

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