Investment Securities (Amortized Cost And Fair Value Of Investment Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Investment [Line Items]
Securities available for sale, Amortized Cost	$ 528,458	$ 543,992
Securities available for sale, Unrealized Gains	1,681	2,928
Securities available for sale, Unrealized Losses	5,166	6,994
Securities available for sale	524,973	539,926
Securities held to maturity, Amortized Cost	516,466	543,338
Securities held to maturity, Unrealized Gains	2,341	2,287
Securities held to maturity, Unrealized Losses	5,824	5,634
Securities held to maturity, fair value	512,983	539,991
U.S. Government Agencies And Government Sponsored Enterprises [Member]
Investment [Line Items]
Securities available for sale, Amortized Cost	163,025	187,325
Securities available for sale, Unrealized Gains	122	512
Securities available for sale, Unrealized Losses	1,258	1,569
Securities available for sale	161,889	186,268
State And Political Subdivisions [Member]
Investment [Line Items]
Securities held to maturity, Amortized Cost	283,557	305,248
Securities held to maturity, Unrealized Gains	2,317	2,127
Securities held to maturity, Unrealized Losses	662	1,616
Securities held to maturity, fair value	285,212	305,759
Collateralized Mortgage Obligations [Member] \| Federal National Mortgage Association [Member]
Investment [Line Items]
Securities available for sale, Amortized Cost	217	16,921
Securities available for sale, Unrealized Gains	1	74
Securities available for sale, Unrealized Losses	1	125
Securities available for sale	217	16,870
Securities held to maturity, Amortized Cost	76,432	83,929
Securities held to maturity, Unrealized Gains		21
Securities held to maturity, Unrealized Losses	1,958	1,573
Securities held to maturity, fair value	74,474	82,377
Collateralized Mortgage Obligations [Member] \| Federal Home Loan Mortgage Corporation [Member]
Investment [Line Items]
Securities available for sale, Amortized Cost	45	5,142
Securities available for sale, Unrealized Losses		65
Securities available for sale	45	5,077
Securities held to maturity, Amortized Cost	93,810	101,025
Securities held to maturity, Unrealized Gains	3	80
Securities held to maturity, Unrealized Losses	2,165	1,827
Securities held to maturity, fair value	91,648	99,278
Collateralized Mortgage Obligations [Member] \| Government National Mortgage Association [Member]
Investment [Line Items]
Securities held to maturity, Amortized Cost	22,881	14,909
Securities held to maturity, Unrealized Gains	5	40
Securities held to maturity, Unrealized Losses	502	162
Securities held to maturity, fair value	22,384	14,787
Collateralized Mortgage Obligations [Member] \| Privately Issued [Member]
Investment [Line Items]
Securities available for sale, Unrealized Gains	976	824
Securities available for sale	976	824
Mortgage-Backed Securities [Member]
Investment [Line Items]
Securities available for sale, Amortized Cost	365,433	356,667
Securities available for sale, Unrealized Gains	1,559	2,225
Securities available for sale, Unrealized Losses	3,908	5,425
Securities available for sale	363,084	353,467
Securities held to maturity, Amortized Cost	232,909	238,090
Securities held to maturity, Unrealized Gains	24	160
Securities held to maturity, Unrealized Losses	5,162	4,018
Securities held to maturity, fair value	227,771	234,232
Mortgage-Backed Securities [Member] \| Federal National Mortgage Association [Member]
Investment [Line Items]
Securities available for sale, Amortized Cost	311,830	288,949
Securities available for sale, Unrealized Gains	313	897
Securities available for sale, Unrealized Losses	3,220	4,413
Securities available for sale	308,923	285,433
Securities held to maturity, Amortized Cost	9,732	10,362
Securities held to maturity, Unrealized Gains	16	1
Securities held to maturity, Unrealized Losses	88	124
Securities held to maturity, fair value	9,660	10,239
Mortgage-Backed Securities [Member] \| Federal Home Loan Mortgage Corporation [Member]
Investment [Line Items]
Securities available for sale, Amortized Cost	41,290	30,182
Securities available for sale, Unrealized Gains	76	114
Securities available for sale, Unrealized Losses	675	807
Securities available for sale	40,691	29,489
Securities held to maturity, Amortized Cost	3,213	3,290
Securities held to maturity, Unrealized Losses	119	150
Securities held to maturity, fair value	3,094	3,140
Mortgage-Backed Securities [Member] \| Government National Mortgage Association [Member]
Investment [Line Items]
Securities available for sale, Amortized Cost	12,051	15,473
Securities available for sale, Unrealized Gains	193	316
Securities available for sale, Unrealized Losses	12	15
Securities available for sale	12,232	15,774
Securities held to maturity, Amortized Cost	26,841	24,575
Securities held to maturity, Unrealized Gains		18
Securities held to maturity, Unrealized Losses	330	182
Securities held to maturity, fair value	$ 26,511	24,411
Asset-Backed Securities [Member]
Investment [Line Items]
Securities available for sale, Unrealized Gains		191
Securities available for sale		$ 191

Line items represent reporting 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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 12
-Sentence Column A

+ Details

Name:	invest_InvestmentLineItems
Namespace Prefix:	invest_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

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
-Paragraph 5
-Subparagraph (aa)
-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
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562

+ Details

Name:	us-gaap_AvailableForSaleSecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesAmortizedCost
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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=82897076&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=75030427&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=82897076&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

+ Details

Name:	us-gaap_HeldToMaturitySecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of accumulated unrealized gain on investments in debt securities classified as held-to-maturity.

+ References

+ Details

Name:	us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity.

+ References

+ Details

Name:	us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value of investments in debt securities classified as held-to-maturity.

+ References

+ Details

Name:	us-gaap_HeldToMaturitySecuritiesFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_USStatesAndPoliticalSubdivisionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_CollateralizedMortgageObligationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_FederalNationalMortgageAssociationCertificatesAndObligationsFNMAMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_FederalHomeLoanMortgageCorporationCertificatesAndObligationsFHLMCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_GovernmentNationalMortgageAssociationCertificatesAndObligationsGNMAMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_MortgageBackedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_AssetBackedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: