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

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

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

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

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Line items represent financial 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.

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No definition available.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance 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 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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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(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB
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-Name Accounting Standards Codification
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-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544

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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

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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- 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.

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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)
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Loans, Leases and Other Real Estate - Allowance for Loan and Lease Losses by Portfolio Segment (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans and Leases	$ 4,228,052	$ 4,156,680
Ending Balance: Individually evaluated for impairment, related allowance	423	505
Ending Balance	35,644	35,455	$ 31,590	$ 31,245
Loans and Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Ending Balance: Individually evaluated for impairment	19,560	22,591
Ending Balance: Collectively evaluated for impairment	4,207,794	4,133,379
Total Loans and Leases	4,228,052	4,156,680
Ending Balance: Individually evaluated for impairment, related allowance	423	505
Ending Balance: Collectively evaluated for impairment, related allowance	35,221	34,950
Ending Balance	35,644	35,455
Commercial, secured by real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans and Leases	2,885,997	2,831,184
Ending Balance: Individually evaluated for impairment, related allowance	386	454
Ending Balance	25,817	25,704	22,083	21,223
Commercial, secured by real estate \| Loans and Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Ending Balance: Individually evaluated for impairment	13,766	17,536
Ending Balance: Collectively evaluated for impairment	2,871,534	2,812,941
Total Loans and Leases	2,885,997	2,831,184
Ending Balance: Individually evaluated for impairment, related allowance	386	454
Ending Balance: Collectively evaluated for impairment, related allowance	25,431	25,250
Ending Balance	25,817	25,704
Commercial, industrial and other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans and Leases	339,665	340,400
Ending Balance: Individually evaluated for impairment, related allowance	9	9
Ending Balance	1,768	2,313	1,792	1,723
Commercial, industrial and other \| Loans and Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Ending Balance: Individually evaluated for impairment	2,107	782
Ending Balance: Collectively evaluated for impairment	337,558	339,618
Total Loans and Leases	339,665	340,400
Ending Balance: Individually evaluated for impairment, related allowance	9	9
Ending Balance: Collectively evaluated for impairment, related allowance	1,759	2,304
Ending Balance	1,768	2,313
Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans and Leases	78,238	75,039
Ending Balance: Individually evaluated for impairment, related allowance	16	30
Ending Balance	1,042	630	502	548
Leases \| Loans and Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Ending Balance: Individually evaluated for impairment	36	65
Ending Balance: Collectively evaluated for impairment	78,202	74,974
Total Loans and Leases	78,238	75,039
Ending Balance: Individually evaluated for impairment, related allowance	16	30
Ending Balance: Collectively evaluated for impairment, related allowance	1,026	600
Ending Balance	1,042	630
Real estate - residential mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans and Leases	323,054	322,880
Ending Balance: Individually evaluated for impairment, related allowance	4	4
Ending Balance	1,589	1,557	1,825	1,964
Real estate - residential mortgage \| Loans and Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Ending Balance: Individually evaluated for impairment	1,200	1,744
Ending Balance: Collectively evaluated for impairment	321,854	321,136
Total Loans and Leases	323,054	322,880
Ending Balance: Individually evaluated for impairment, related allowance	4	4
Ending Balance: Collectively evaluated for impairment, related allowance	1,585	1,553
Ending Balance	1,589	1,557
Real estate - construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans and Leases	283,378	264,908
Ending Balance: Individually evaluated for impairment, related allowance	0	0
Ending Balance	2,932	2,731	2,378	2,352
Real estate - construction \| Loans and Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Ending Balance: Individually evaluated for impairment	1,471	1,471
Ending Balance: Collectively evaluated for impairment	281,907	263,437
Total Loans and Leases	283,378	264,908
Ending Balance: Individually evaluated for impairment, related allowance	0	0
Ending Balance: Collectively evaluated for impairment, related allowance	2,932	2,731
Ending Balance	2,932	2,731
Home equity and consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans and Leases	317,720	322,269
Ending Balance: Individually evaluated for impairment, related allowance	8	8
Ending Balance	2,496	2,520	$ 3,010	$ 3,435
Home equity and consumer \| Loans and Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Ending Balance: Individually evaluated for impairment	980	993
Ending Balance: Collectively evaluated for impairment	316,739	321,273
Total Loans and Leases	317,720	322,269
Ending Balance: Individually evaluated for impairment, related allowance	8	8
Ending Balance: Collectively evaluated for impairment, related allowance	2,488	2,512
Ending Balance	2,496	2,520
Financial Asset Acquired with Credit Deterioration \| Loans and Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Ending Balance: Loans acquired with deteriorated credit quality	698	710
Financial Asset Acquired with Credit Deterioration \| Commercial, secured by real estate \| Loans and Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Ending Balance: Loans acquired with deteriorated credit quality	697	707
Financial Asset Acquired with Credit Deterioration \| Commercial, industrial and other \| Loans and Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Ending Balance: Loans acquired with deteriorated credit quality	0	0
Financial Asset Acquired with Credit Deterioration \| Leases \| Loans and Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Ending Balance: Loans acquired with deteriorated credit quality	0	0
Financial Asset Acquired with Credit Deterioration \| Real estate - residential mortgage \| Loans and Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Ending Balance: Loans acquired with deteriorated credit quality	0	0
Financial Asset Acquired with Credit Deterioration \| Real estate - construction \| Loans and Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Ending Balance: Loans acquired with deteriorated credit quality	0	0
Financial Asset Acquired with Credit Deterioration \| Home equity and consumer \| Loans and Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Ending Balance: Loans acquired with deteriorated credit quality	$ 1	$ 3