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Allowance for Loan Losses - Recorded Investment in Consumer Loan Classes by Performing and Nonperforming Status (Details) - Consumer - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivables, recorded investment	$ 1,242,112	$ 1,257,855
Percentage of Total	100.00%	100.00%
Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivables, recorded investment	$ 1,232,080	$ 1,246,904
Percentage of Total	99.20%	99.10%
Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivables, recorded investment	$ 10,032	$ 10,951
Percentage of Total	0.80%	0.90%
Residential mortgage
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivables, recorded investment	$ 698,440	$ 698,774
Percentage of Total	100.00%	100.00%
Residential mortgage | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivables, recorded investment	$ 692,328	$ 691,609
Percentage of Total	99.10%	99.00%
Residential mortgage | Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivables, recorded investment	$ 6,112	$ 7,165
Percentage of Total	0.90%	1.00%
Home equity
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivables, recorded investment	$ 471,622	$ 487,326
Percentage of Total	100.00%	100.00%
Home equity | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivables, recorded investment	$ 467,751	$ 483,611
Percentage of Total	99.20%	99.20%
Home equity | Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivables, recorded investment	$ 3,871	$ 3,715
Percentage of Total	0.80%	0.80%
Installment and other consumer
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivables, recorded investment	$ 66,638	$ 67,204
Percentage of Total	100.00%	100.00%
Installment and other consumer | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivables, recorded investment	$ 66,589	$ 67,133
Percentage of Total	99.90%	99.90%
Installment and other consumer | Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivables, recorded investment	$ 49	$ 71
Percentage of Total	0.10%	0.10%
Consumer construction
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivables, recorded investment	$ 5,412	$ 4,551
Percentage of Total	100.00%	100.00%
Consumer construction | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivables, recorded investment	$ 5,412	$ 4,551
Percentage of Total	100.00%	100.00%
Consumer construction | Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivables, recorded investment	$ 0	$ 0
Percentage of Total	0.00%	0.00%

X

- Definition

Loans and leases receivable gross carrying amount consumer percentage.

+ References

No definition available.

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- Definition

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+ References

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- Definition

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://fasb.org/us-gaap/role/ref/legacyRef
-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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