Allowance for loan losses ending allowance balance attributable to loans.

No definition available.

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- Definition

Financing receivable allowance for credit losses modifications recorded investment.

+ References

No definition available.

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- Definition

Financing receivables allowance for credit loss additional information for loans.

+ References

No definition available.

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- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

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- Definition

Amount after allowance and 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. Includes loans held for sale. 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 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(a))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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- Definition

Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ 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 210.5-02.3)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Loans - Allowance for Loan Losses and Recorded Investment in Loans by Portfolio Segment (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Ending allowance balance attributable to loans:
Allowance for loan losses, Individually evaluated for impairment	$ 47	$ 1,184
Allowance for loan losses, Collectively evaluated for impairment	13,957	12,807
Allowance for loan losses, Modified in a troubled debt restructuring	5,689	2,339
Acquired with deteriorated credit quality	19,693	16,330	$ 16,737	$ 17,373
Loans:
Loans individually evaluated for impairment	1,238	6,951
Loans collectively evaluated for impairment	2,130,228	1,856,452
Acquired with deteriorated credit quality	1,349,203	1,142,626
Loans modified in a troubled debt restructuring	17,303	11,831
Total ending loans balance	2,149,848	1,876,966
Receivables Acquired with Deteriorated Credit Quality [Member]
Ending allowance balance attributable to loans:
Acquired with deteriorated credit quality	0	0
Loans:
Acquired with deteriorated credit quality	1,079	1,732
Commercial, Industrial, and Agricultural [Member]
Ending allowance balance attributable to loans:
Allowance for loan losses, Individually evaluated for impairment	47	188
Allowance for loan losses, Collectively evaluated for impairment	5,868	5,115
Allowance for loan losses, Modified in a troubled debt restructuring	245	125
Acquired with deteriorated credit quality	6,160	5,428	6,035	7,114
Loans:
Loans individually evaluated for impairment	1,187	775
Loans collectively evaluated for impairment	742,738	564,180
Acquired with deteriorated credit quality	749,138	567,800
Loans modified in a troubled debt restructuring	5,213	2,640
Total ending loans balance	749,138	567,800
Commercial, Industrial, and Agricultural [Member] \| Receivables Acquired with Deteriorated Credit Quality [Member]
Ending allowance balance attributable to loans:
Acquired with deteriorated credit quality	0	0
Loans:
Acquired with deteriorated credit quality	0	205
Commercial Mortgages [Member]
Ending allowance balance attributable to loans:
Allowance for loan losses, Individually evaluated for impairment	0	996
Allowance for loan losses, Collectively evaluated for impairment	3,563	3,543
Allowance for loan losses, Modified in a troubled debt restructuring	5,444	2,214
Acquired with deteriorated credit quality	9,007	6,753	5,605	5,310
Loans:
Loans individually evaluated for impairment	51	6,176
Loans collectively evaluated for impairment	586,845	557,932
Acquired with deteriorated credit quality	600,065	574,826
Loans modified in a troubled debt restructuring	12,090	9,191
Total ending loans balance	600,065	574,826
Commercial Mortgages [Member] \| Receivables Acquired with Deteriorated Credit Quality [Member]
Ending allowance balance attributable to loans:
Acquired with deteriorated credit quality	0	0
Loans:
Acquired with deteriorated credit quality	1,079	1,527
Residential Real Estate [Member]
Ending allowance balance attributable to loans:
Allowance for loan losses, Individually evaluated for impairment	0	0
Allowance for loan losses, Collectively evaluated for impairment	2,033	1,653
Allowance for loan losses, Modified in a troubled debt restructuring	0	0
Acquired with deteriorated credit quality	2,033	1,653	2,475	2,479
Loans:
Loans individually evaluated for impairment	0	0
Loans collectively evaluated for impairment	713,347	652,883
Loans modified in a troubled debt restructuring	0	0
Total ending loans balance	713,347	652,883
Residential Real Estate [Member] \| Receivables Acquired with Deteriorated Credit Quality [Member]
Ending allowance balance attributable to loans:
Acquired with deteriorated credit quality	0	0
Loans:
Acquired with deteriorated credit quality	0	0
Consumer [Member]
Ending allowance balance attributable to loans:
Allowance for loan losses, Individually evaluated for impairment	0	0
Allowance for loan losses, Collectively evaluated for impairment	2,179	2,215
Allowance for loan losses, Modified in a troubled debt restructuring	0	0
Acquired with deteriorated credit quality	2,179	2,215	2,371	2,205
Loans:
Loans individually evaluated for impairment	0	0
Loans collectively evaluated for impairment	80,193	74,816
Loans modified in a troubled debt restructuring	0	0
Total ending loans balance	80,193	74,816
Consumer [Member] \| Receivables Acquired with Deteriorated Credit Quality [Member]
Ending allowance balance attributable to loans:
Acquired with deteriorated credit quality	0	0
Loans:
Acquired with deteriorated credit quality	0	0
Credit Cards [Member]
Ending allowance balance attributable to loans:
Allowance for loan losses, Individually evaluated for impairment	0	0
Allowance for loan losses, Collectively evaluated for impairment	120	93
Allowance for loan losses, Modified in a troubled debt restructuring	0	0
Acquired with deteriorated credit quality	120	93	90	71
Loans:
Loans individually evaluated for impairment	0	0
Loans collectively evaluated for impairment	6,753	6,046
Loans modified in a troubled debt restructuring	0	0
Total ending loans balance	6,753	6,046
Credit Cards [Member] \| Receivables Acquired with Deteriorated Credit Quality [Member]
Ending allowance balance attributable to loans:
Acquired with deteriorated credit quality	0	0
Loans:
Acquired with deteriorated credit quality	0	0
Overdrafts [Member]
Ending allowance balance attributable to loans:
Allowance for loan losses, Individually evaluated for impairment	0	0
Allowance for loan losses, Collectively evaluated for impairment	194	188
Allowance for loan losses, Modified in a troubled debt restructuring	0	0
Acquired with deteriorated credit quality	194	188	$ 161	$ 194
Loans:
Loans individually evaluated for impairment	0	0
Loans collectively evaluated for impairment	352	595
Loans modified in a troubled debt restructuring	0	0
Total ending loans balance	352	595
Overdrafts [Member] \| Receivables Acquired with Deteriorated Credit Quality [Member]
Ending allowance balance attributable to loans:
Acquired with deteriorated credit quality	0	0
Loans:
Acquired with deteriorated credit quality	$ 0	$ 0