Allowance Balances [Abstract]

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- Definition

Loan Balance [Abstract]

+ References

No definition available.

+ Details

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- Definition

Loans and Leases Receivable

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

+ Details

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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

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Period Type:	instant

- Definition

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

+ References

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- Definition

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

+ References

+ Details

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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

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- Details

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Loans and Allowance - Allowance for Credit Losses and Loan Portfolio by Loan Segment (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Allowance Balances:
Individually evaluated for impairment	$ 1,317	$ 1,637
Collectively evaluated for impairment	75,103	73,395
Total Allowance for Loan Losses	76,420	75,032	$ 68,225	$ 66,037
Loan Balance [Abstract]
Individually evaluated for impairment	22,164	23,211
Collectively evaluated for impairment	6,855,540	6,703,034
Loans	6,901,696	6,751,199
Loans acquired with deteriorated credit quality
Loan Balance [Abstract]
Loans	23,992	24,954
Commercial
Allowance Balances:
Individually evaluated for impairment	143	666
Collectively evaluated for impairment	30,625	29,752
Total Allowance for Loan Losses	30,768	30,418	28,524	27,696
Loan Balance [Abstract]
Individually evaluated for impairment	2,914	3,345
Collectively evaluated for impairment	2,042,193	2,005,275
Loans	2,047,992	2,010,041
Commercial \| Loans acquired with deteriorated credit quality
Loan Balance [Abstract]
Loans	2,885	1,421
Commercial Real Estate
Allowance Balances:
Individually evaluated for impairment	758	567
Collectively evaluated for impairment	26,947	26,776
Total Allowance for Loan Losses	27,705	27,343	24,320	23,661
Loan Balance [Abstract]
Individually evaluated for impairment	16,501	17,432
Collectively evaluated for impairment	3,268,036	3,135,481
Loans	3,304,087	3,174,910
Commercial Real Estate \| Loans acquired with deteriorated credit quality
Loan Balance [Abstract]
Loans	19,550	21,997
Consumer
Allowance Balances:
Individually evaluated for impairment
Collectively evaluated for impairment	3,896	3,732
Total Allowance for Loan Losses	3,896	3,732	3,120	2,923
Loan Balance [Abstract]
Individually evaluated for impairment	11	5
Collectively evaluated for impairment	88,224	86,930
Loans	88,235	86,935
Consumer \| Loans acquired with deteriorated credit quality
Loan Balance [Abstract]
Loans
Residential
Allowance Balances:
Individually evaluated for impairment	416	404
Collectively evaluated for impairment	13,633	13,133
Total Allowance for Loan Losses	14,049	13,537	12,259	11,755
Loan Balance [Abstract]
Individually evaluated for impairment	2,738	2,429
Collectively evaluated for impairment	1,454,894	1,472,821
Loans	1,459,189	1,476,786
Residential \| Loans acquired with deteriorated credit quality
Loan Balance [Abstract]
Loans	1,557	1,536
Lease financing receivables, net of unearned income
Allowance Balances:
Individually evaluated for impairment
Collectively evaluated for impairment	2	2
Total Allowance for Loan Losses	2	2	$ 2	$ 2
Loan Balance [Abstract]
Individually evaluated for impairment
Collectively evaluated for impairment	2,193	2,527
Loans	2,193	2,527
Lease financing receivables, net of unearned income \| Loans acquired with deteriorated credit quality
Loan Balance [Abstract]
Loans