No definition available.

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- Definition

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

+ References

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment
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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

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

Name:	us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment
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- Definition

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

+ References

+ Details

Name:	us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment
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Data Type:	xbrli:monetaryItemType
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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
-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

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

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L.1)
-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544

+ Details

Name:	us-gaap_LoansAndLeasesReceivableAllowance
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Balance Type:	credit
Period Type:	instant

- 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

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

+ Details

Name:	us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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- Details

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- Details

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- Details

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Allowance for Loan Losses and Credit Quality of Loans, Allowance for Loan Losses and Recorded Investment in Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Allowance for loan losses	$ 70,200	$ 69,500	$ 65,700	$ 65,200
Allowance for loans individually evaluated for impairment	42	57
Allowance for loans collectively evaluated for impairment	70,158	69,443
Ending balance of loans	6,647,124	6,584,773
Commercial Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Allowance for loan losses	28,190	27,606	24,727	25,444
Allowance for loans individually evaluated for impairment	42	57
Allowance for loans collectively evaluated for impairment	28,148	27,549
Ending balance of loans	3,048,003	3,028,269
Consumer Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Allowance for loan losses	36,973	36,830	34,769	33,375
Allowance for loans individually evaluated for impairment	0	0
Allowance for loans collectively evaluated for impairment	36,973	36,830
Ending balance of loans	2,266,054	2,234,809
Residential Real Estate Mortgages [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Allowance for loan losses	5,037	5,064	$ 6,204	$ 6,381
Allowance for loans individually evaluated for impairment	0	0
Allowance for loans collectively evaluated for impairment	5,037	5,064
Ending balance of loans	1,333,067	1,321,695
Originated Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Ending balance of loans	6,269,415	6,183,082
Ending balance of loans individually evaluated for impairment	21,082	21,138
Ending balance of loans collectively evaluated for impairment	6,248,333	6,161,944
Originated Loans [Member] \| Commercial Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Ending balance of loans	2,875,083	2,840,956
Ending balance of loans individually evaluated for impairment	6,006	5,876
Ending balance of loans collectively evaluated for impairment	2,869,077	2,835,080
Originated Loans [Member] \| Consumer Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Ending balance of loans	2,225,388	2,190,903
Ending balance of loans individually evaluated for impairment	8,305	8,432
Ending balance of loans collectively evaluated for impairment	2,217,083	2,182,471
Originated Loans [Member] \| Residential Real Estate Mortgages [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Ending balance of loans	1,168,944	1,151,223
Ending balance of loans individually evaluated for impairment	6,771	6,830
Ending balance of loans collectively evaluated for impairment	1,162,173	1,144,393
Acquired Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Allowance for loan losses	0	0
Ending balance of loans	377,709	401,691
Ending balance of loans collectively evaluated for impairment	377,709	401,691
Acquired Loans [Member] \| Commercial Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Ending balance of loans	172,920	187,313
Ending balance of loans collectively evaluated for impairment	172,920	187,313
Acquired Loans [Member] \| Consumer Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Ending balance of loans	40,666	43,906
Ending balance of loans collectively evaluated for impairment	40,666	43,906
Acquired Loans [Member] \| Residential Real Estate Mortgages [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Ending balance of loans	164,123	170,472
Ending balance of loans collectively evaluated for impairment	$ 164,123	$ 170,472