Loans (Acquired and Non-Acquired Loans) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
Loans receivables	$ 1,307,737	$ 1,150,044	$ 1,145,406
Net deferred costs (fees)	917	1,086
Total loans, net of deferred costs	$ 1,308,654	$ 1,151,130
Percentage Status Of Loan	100.00%	100.00%
Deferred loan fees and premiums, percentage	0.07%	0.09%
County First Bank Acquisition [Member]
Loans receivables	$ 110,653
Percentage Status Of Loan	8.46%	0.00%
Non Acquired [Member]
Loans receivables	$ 1,197,084	$ 1,150,044
Percentage Status Of Loan	91.54%	100.00%
PCI Loans [Member]
Loans receivables	$ 3,511
Total loans, net of deferred costs	$ 3,511
Percentage Status Of Loan	0.20%
PCI Loans [Member] \| County First Bank Acquisition [Member]
Loans receivables	$ 3,511
Percentage Status Of Loan	0.27%	0.00%
All Other Loans [Member]
Loans receivables	$ 1,304,226
Net deferred costs (fees)	917
Total loans, net of deferred costs	1,305,143
All Other Loans [Member] \| County First Bank Acquisition [Member]
Loans receivables	$ 107,142
Percentage Status Of Loan	8.19%	0.00%

Loans And Leases Receivable Deferred Loan Fees And Premuims Percentage

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- Definition

Percentage status of loan.

+ References

No definition available.

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- Definition

Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84159169&loc=d3e10152-111534

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=84165051&loc=d3e45377-112738

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

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