Investments (Held-To-Maturity Securities Disclosure) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Dec. 31, 2015
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 163,346	$ 201,054
Net Unrealized Gains (Losses)	227	300
Carrying Value	163,573	201,354
Unrecognized Holding Gains	7,686	8,190
Unrecognized Holding Losses	0	0
HTM, Fair Value	$ 171,259	209,544
Held-to-maturity Securities Average Duration	1 year 7 months 18 days
Obligations of States and Political Subdivisions [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 138,203	175,269
Net Unrealized Gains (Losses)	674	848
Carrying Value	138,877	176,117
Unrecognized Holding Gains	5,031	5,763
Unrecognized Holding Losses	0	0
HTM, Fair Value	143,908	181,880
Corporate Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	19,829	20,228
Net Unrealized Gains (Losses)	(180)	(185)
Carrying Value	19,649	20,043
Unrecognized Holding Gains	2,299	1,972
Unrecognized Holding Losses	0	0
HTM, Fair Value	21,948	22,015
Asset-Backed Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	808	1,030
Net Unrealized Gains (Losses)	(70)	(120)
Carrying Value	738	910
Unrecognized Holding Gains	67	118
Unrecognized Holding Losses	0	0
HTM, Fair Value	805	1,028
Commercial Mortgage Backed Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	4,506	4,527
Net Unrealized Gains (Losses)	(197)	(243)
Carrying Value	4,309	4,284
Unrecognized Holding Gains	289	337
Unrecognized Holding Losses	0	0
HTM, Fair Value	$ 4,598	$ 4,621

Held to maturity securities average duration.

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- Definition

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
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

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-Name Accounting Standards Codification
-Topic 320
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-Section 25
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.6)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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