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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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- 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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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

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Period Type:	instant

- Details

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Loans and Allowance - Allowance for Credit Losses and Loan Portfolio by Loan Segment (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016
Allowance Balances:
Individually evaluated for impairment	$ 497		$ 1,637
Collectively evaluated for impairment	77,046		73,395
Total Allowance for Loan Losses	77,543	$ 76,420	75,032	$ 70,471	$ 68,225	$ 66,037
Loan Balance [Abstract]
Individually evaluated for impairment	14,076		23,211
Collectively evaluated for impairment	7,043,954		6,703,034
Loans	7,081,059		6,751,199
Loans acquired with deteriorated credit quality
Loan Balance [Abstract]
Loans	23,029		24,954
Commercial
Allowance Balances:
Individually evaluated for impairment	76		666
Collectively evaluated for impairment	31,389		29,752
Total Allowance for Loan Losses	31,465	30,768	30,418	28,906	28,524	27,696
Loan Balance [Abstract]
Individually evaluated for impairment	1,746		3,345
Collectively evaluated for impairment	2,129,626		2,005,275
Loans	2,134,238		2,010,041
Commercial \| Loans acquired with deteriorated credit quality
Loan Balance [Abstract]
Loans	2,866		1,421
Commercial Real Estate
Allowance Balances:
Individually evaluated for impairment			567
Collectively evaluated for impairment	27,731		26,776
Total Allowance for Loan Losses	27,731	27,705	27,343	25,236	24,320	23,661
Loan Balance [Abstract]
Individually evaluated for impairment	10,251		17,432
Collectively evaluated for impairment	3,338,815		3,135,481
Loans	3,367,648		3,174,910
Commercial Real Estate \| Loans acquired with deteriorated credit quality
Loan Balance [Abstract]
Loans	18,582		21,997
Consumer
Allowance Balances:
Individually evaluated for impairment
Collectively evaluated for impairment	3,921		3,732
Total Allowance for Loan Losses	3,921	3,896	3,732	3,372	3,120	2,923
Loan Balance [Abstract]
Individually evaluated for impairment	10		5
Collectively evaluated for impairment	92,799		86,930
Loans	92,809		86,935
Consumer \| Loans acquired with deteriorated credit quality
Loan Balance [Abstract]
Loans
Residential
Allowance Balances:
Individually evaluated for impairment	421		404
Collectively evaluated for impairment	14,003		13,133
Total Allowance for Loan Losses	14,424	14,049	13,537	12,955	12,259	11,755
Loan Balance [Abstract]
Individually evaluated for impairment	2,069		2,429
Collectively evaluated for impairment	1,480,769		1,472,821
Loans	1,484,419		1,476,786
Residential \| Loans acquired with deteriorated credit quality
Loan Balance [Abstract]
Loans	1,581		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	$ 2	$ 2
Loan Balance [Abstract]
Individually evaluated for impairment
Collectively evaluated for impairment	1,945		2,527
Loans	1,945		2,527
Lease financing receivables, net of unearned income \| Loans acquired with deteriorated credit quality
Loan Balance [Abstract]
Loans