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Investments (Held-To-Maturity Securities Disclosure) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 72,448	$ 101,397
Net Unrealized Gains (Losses)	66	159
Carrying Value	72,514	101,556
Unrecognized Holding Gains	3,026	3,813
Unrecognized Holding Losses	0	(158)
Held-to-maturity Securities, Fair Value	75,540	105,211
Obligations of States and Political Subdivisions [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	53,734	77,466
Net Unrealized Gains (Losses)	185	317
Carrying Value	53,919	77,783
Unrecognized Holding Gains	1,703	2,133
Unrecognized Holding Losses	0	0
Held-to-maturity Securities, Fair Value	55,622	79,916
Corporate Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	18,714	22,711
Net Unrealized Gains (Losses)	(119)	(143)
Carrying Value	18,595	22,568
Unrecognized Holding Gains	1,323	1,665
Unrecognized Holding Losses	0	(158)
Held-to-maturity Securities, Fair Value	$ 19,918	24,075
Commercial Mortgage Backed Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost		1,220
Net Unrealized Gains (Losses)		(15)
Carrying Value		1,205
Unrecognized Holding Gains		15
Unrecognized Holding Losses		0
Held-to-maturity Securities, Fair Value		$ 1,220

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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.

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+ References

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-Publisher FASB
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