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Investments (Held-To-Maturity Securities Disclosure) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 64,977	$ 101,397
Net Unrealized Gains (Losses)	12	159
HTM, Carrying Value	64,989	101,556
Unrecognized Holding Gains	2,727	3,813
Unrecognized Holding Losses	0	(158)
Held-to-maturity Securities, Fair Value	67,716	105,211
Obligations of States and Political Subdivisions [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	46,551	77,466
Net Unrealized Gains (Losses)	130	317
HTM, Carrying Value	46,681	77,783
Unrecognized Holding Gains	1,442	2,133
Unrecognized Holding Losses	0	0
Held-to-maturity Securities, Fair Value	48,123	79,916
Corporate Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	18,426	22,711
Net Unrealized Gains (Losses)	(118)	(143)
HTM, Carrying Value	18,308	22,568
Unrecognized Holding Gains	1,285	1,665
Unrecognized Holding Losses	0	(158)
Held-to-maturity Securities, Fair Value	$ 19,593	24,075
Commercial Mortgage Backed Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost		1,220
Net Unrealized Gains (Losses)		(15)
HTM, Carrying Value		1,205
Unrecognized Holding Gains		15
Unrecognized Holding Losses		0
Held-to-maturity Securities, Fair Value		$ 1,220

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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.

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