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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- Details

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Allowance for Loan Losses and Credit Quality of Loans, Allowance for Loan Losses and Recorded Investment (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Allowance for loan losses	$ 69,500	$ 65,200	$ 63,018	$ 66,359
Allowance for loans individually evaluated for impairment	57	1,517
Allowance for loans collectively evaluated for impairment	69,443	63,683
Ending balance of loans	6,584,773	6,198,057
Commercial Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Allowance for loan losses	27,606	25,444	25,545	32,433
Allowance for loans individually evaluated for impairment	57	1,517
Allowance for loans collectively evaluated for impairment	27,549	23,927
Ending balance of loans	3,028,269	2,786,002
Consumer Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Allowance for loan losses	36,830	33,375	29,253	26,720
Allowance for loans individually evaluated for impairment	0	0
Allowance for loans collectively evaluated for impairment	36,830	33,375
Ending balance of loans	2,234,809	2,149,441
Residential Real Estate Mortgages [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Allowance for loan losses	5,064	6,381	7,960	7,130
Allowance for loans individually evaluated for impairment	0	0
Allowance for loans collectively evaluated for impairment	5,064	6,381
Ending balance of loans	1,321,695	1,262,614
Unallocated [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Allowance for loan losses	0	0	$ 260	$ 76
Originated Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Ending balance of loans	6,183,082	5,697,963
Ending balance of loans individually evaluated for impairment	21,138	27,669
Ending balance of loans collectively evaluated for impairment	6,161,944	5,670,294
Originated Loans [Member] \| Commercial Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Ending balance of loans	2,840,956	2,548,384
Ending balance of loans individually evaluated for impairment	5,876	13,070
Ending balance of loans collectively evaluated for impairment	2,835,080	2,535,314
Originated Loans [Member] \| Consumer Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Ending balance of loans	2,190,903	2,086,436
Ending balance of loans individually evaluated for impairment	8,432	8,488
Ending balance of loans collectively evaluated for impairment	2,182,471	2,077,948
Originated Loans [Member] \| Residential Real Estate Mortgages [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Ending balance of loans	1,151,223	1,063,143
Ending balance of loans individually evaluated for impairment	6,830	6,111
Ending balance of loans collectively evaluated for impairment	1,144,393	1,057,032
Acquired Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Allowance for loan losses	0	700
Ending balance of loans	401,691	500,094
Ending balance of loans individually evaluated for impairment		1,205
Ending balance of loans collectively evaluated for impairment	401,691	498,889
Acquired Loans [Member] \| Commercial Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Ending balance of loans	187,313	237,618
Ending balance of loans individually evaluated for impairment		1,205
Ending balance of loans collectively evaluated for impairment	187,313	236,413
Acquired Loans [Member] \| Consumer Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Ending balance of loans	43,906	63,005
Ending balance of loans individually evaluated for impairment		0
Ending balance of loans collectively evaluated for impairment	43,906	63,005
Acquired Loans [Member] \| Residential Real Estate Mortgages [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Ending balance of loans	170,472	199,471
Ending balance of loans individually evaluated for impairment		0
Ending balance of loans collectively evaluated for impairment	$ 170,472	$ 199,471