Investments (Unrealized Gain (loss) On Investments) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	$ 134,412
Gross unrealized gains	616
Gross unrealized losses	(1,706)
Available for sale	133,322	$ 126,971
Before Adoption Of ASU 2016-01 [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost		127,182
Gross unrealized gains		1,200
Gross unrealized losses		(1,046)
Available for sale		127,336
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost		164
Gross unrealized gains		201
Available for sale		365
U.S. Government And Agency Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	10,534	11,451
Gross unrealized gains	22	64
Gross unrealized losses	(74)	(43)
Available for sale	10,482	11,472
Municipal Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	63,520	57,374
Gross unrealized gains	409	650
Gross unrealized losses	(619)	(252)
Available for sale	63,310	57,772
Trust Preferred Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	6,007	6,000
Gross unrealized gains	1
Gross unrealized losses	(159)	(183)
Available for sale	5,849	5,817
Agency Mortgage-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	53,494	51,307
Gross unrealized gains	105	197
Gross unrealized losses	(852)	(567)
Available for sale	52,747	50,937
Private-Label Mortgage-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	830	858
Gross unrealized gains	79	88
Available for sale	909	946
Asset-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	27	28
Gross unrealized losses	(2)	(1)
Available for sale	$ 25	$ 27

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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