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Investments (Held-To-Maturity Securities Disclosure) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 84,728	$ 101,397
Net Unrealized Gains (Losses)	108	159
Carrying Value	84,836	101,556
Unrecognized Holding Gains	3,595	3,813
Unrecognized Holding Losses	(92)	(158)
Held-to-maturity Securities, Fair Value	88,339	105,211
Obligations of States and Political Subdivisions [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	62,534	77,466
Net Unrealized Gains (Losses)	245	317
Carrying Value	62,779	77,783
Unrecognized Holding Gains	1,981	2,133
Unrecognized Holding Losses	0	0
Held-to-maturity Securities, Fair Value	64,760	79,916
Corporate Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	22,194	22,711
Net Unrealized Gains (Losses)	(137)	(143)
Carrying Value	22,057	22,568
Unrecognized Holding Gains	1,614	1,665
Unrecognized Holding Losses	(92)	(158)
Held-to-maturity Securities, Fair Value	$ 23,579	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

X

- 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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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