Investments (Held-To-Maturity Securities Disclosure) (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2016	Dec. 31, 2015
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 130,278	$ 201,054
Net Unrealized Gains (Losses)	194	300
Carrying Value	130,472	201,354
Unrecognized Holding Gains	5,622	8,190
Unrecognized Holding Losses	0	0
Held-to-maturity Securities, Fair Value	$ 136,094	209,544
Held-to-maturity Securities Average Duration	1 year 7 months
Obligations of States and Political Subdivisions [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 104,159	175,269
Net Unrealized Gains (Losses)	414	848
Carrying Value	104,573	176,117
Unrecognized Holding Gains	3,256	5,763
Unrecognized Holding Losses	0	0
Held-to-maturity Securities, Fair Value	107,829	181,880
Corporate Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	23,722	20,228
Net Unrealized Gains (Losses)	(165)	(185)
Carrying Value	23,557	20,043
Unrecognized Holding Gains	2,294	1,972
Unrecognized Holding Losses	0	0
Held-to-maturity Securities, Fair Value	25,851	22,015
Asset-Backed Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	51	1,030
Net Unrealized Gains (Losses)	0	(120)
Carrying Value	51	910
Unrecognized Holding Gains	0	118
Unrecognized Holding Losses	0	0
Held-to-maturity Securities, Fair Value	51	1,028
Commercial Mortgage Backed Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	2,346	4,527
Net Unrealized Gains (Losses)	(55)	(243)
Carrying Value	2,291	4,284
Unrecognized Holding Gains	72	337
Unrecognized Holding Losses	0	0
Held-to-maturity Securities, Fair Value	$ 2,363	$ 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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- Definition

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-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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