Allowance for Loan Losses - Investments in Loans Considered to be Impaired and Related Information on Impaired Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Impaired [Line Items]
With a related allowance recorded, Recorded Investment	$ 991	$ 618
With a related allowance recorded, Unpaid Principal Balance	2,460	1,468
With a related allowance recorded, Related Allowance	798	37
Without a related allowance recorded, Recorded Investment	40,944	45,032
Without a related allowance, Unpaid Principal Balance	48,539	50,286
Without a related allowance recorded, Related Allowance	0	0
Impaired financing receivables	41,935	45,650
Impaired Financing Receivable, Unpaid Principal Balance, Total	50,999	51,754
Impaired Financing Receivable, Related Allowance, Total	798	37
Without a related allowance recorded, Average Recorded Investment	43,334	46,638
Without a related allowance recorded, Interest Income Recognized	990	1,741
With a related allowance recorded, Average Recorded Investment	2,468	956
With a related allowance recorded, Interest Income Recognized	2	7
Impaired Financing Receivable, Average Recorded Investment, Total	45,802	47,594
Impaired Financing Receivable, Interest Income Recognized, Total	992	1,748
Commercial Real Estate
Financing Receivable, Impaired [Line Items]
With a related allowance recorded, Recorded Investment	0	0
With a related allowance recorded, Unpaid Principal Balance	0	0
With a related allowance recorded, Related Allowance	0	0
Without a related allowance recorded, Recorded Investment	16,352	12,661
Without a related allowance, Unpaid Principal Balance	17,654	13,157
Without a related allowance recorded, Related Allowance	0	0
Impaired financing receivables	16,352	12,661
Impaired Financing Receivable, Unpaid Principal Balance, Total	17,654	13,157
Impaired Financing Receivable, Related Allowance, Total	0	0
Without a related allowance recorded, Average Recorded Investment	17,496	14,622
Without a related allowance recorded, Interest Income Recognized	144	597
With a related allowance recorded, Average Recorded Investment	0	0
With a related allowance recorded, Interest Income Recognized	0	0
Impaired Financing Receivable, Average Recorded Investment, Total	17,496	14,622
Impaired Financing Receivable, Interest Income Recognized, Total	144	597
Commercial and Industrial
Financing Receivable, Impaired [Line Items]
With a related allowance recorded, Recorded Investment	964	0
With a related allowance recorded, Unpaid Principal Balance	2,433	0
With a related allowance recorded, Related Allowance	771	0
Without a related allowance recorded, Recorded Investment	5,902	14,417
Without a related allowance, Unpaid Principal Balance	7,699	15,220
Without a related allowance recorded, Related Allowance	0	0
Impaired financing receivables	6,866	14,417
Impaired Financing Receivable, Unpaid Principal Balance, Total	10,132	15,220
Impaired Financing Receivable, Related Allowance, Total	771	0
Without a related allowance recorded, Average Recorded Investment	6,141	14,416
Without a related allowance recorded, Interest Income Recognized	160	450
With a related allowance recorded, Average Recorded Investment	2,438	0
With a related allowance recorded, Interest Income Recognized	0	0
Impaired Financing Receivable, Average Recorded Investment, Total	8,579	14,416
Impaired Financing Receivable, Interest Income Recognized, Total	160	450
Commercial Construction
Financing Receivable, Impaired [Line Items]
With a related allowance recorded, Recorded Investment	0	500
With a related allowance recorded, Unpaid Principal Balance	0	1,350
With a related allowance recorded, Related Allowance	0	3
Without a related allowance recorded, Recorded Investment	6,613	10,998
Without a related allowance, Unpaid Principal Balance	10,306	14,200
Without a related allowance recorded, Related Allowance	0	0
Impaired financing receivables	6,613	11,498
Impaired Financing Receivable, Unpaid Principal Balance, Total	10,306	15,550
Impaired Financing Receivable, Related Allowance, Total	0	3
Without a related allowance recorded, Average Recorded Investment	7,723	10,581
Without a related allowance recorded, Interest Income Recognized	162	329
With a related allowance recorded, Average Recorded Investment	0	834
With a related allowance recorded, Interest Income Recognized	0	0
Impaired Financing Receivable, Average Recorded Investment, Total	7,723	11,415
Impaired Financing Receivable, Interest Income Recognized, Total	162	329
Consumer Real Estate
Financing Receivable, Impaired [Line Items]
With a related allowance recorded, Recorded Investment	26	116
With a related allowance recorded, Unpaid Principal Balance	26	116
With a related allowance recorded, Related Allowance	26	32
Without a related allowance recorded, Recorded Investment	12,053	6,845
Without a related allowance, Unpaid Principal Balance	12,849	7,521
Without a related allowance recorded, Related Allowance	0	0
Impaired financing receivables	12,079	6,961
Impaired Financing Receivable, Unpaid Principal Balance, Total	12,875	7,637
Impaired Financing Receivable, Related Allowance, Total	26	32
Without a related allowance recorded, Average Recorded Investment	11,939	6,902
Without a related allowance recorded, Interest Income Recognized	523	364
With a related allowance recorded, Average Recorded Investment	28	120
With a related allowance recorded, Interest Income Recognized	2	7
Impaired Financing Receivable, Average Recorded Investment, Total	11,967	7,022
Impaired Financing Receivable, Interest Income Recognized, Total	525	371
Other Consumer
Financing Receivable, Impaired [Line Items]
With a related allowance recorded, Recorded Investment	1	2
With a related allowance recorded, Unpaid Principal Balance	1	2
With a related allowance recorded, Related Allowance	1	2
Without a related allowance recorded, Recorded Investment	24	111
Without a related allowance, Unpaid Principal Balance	31	188
Without a related allowance recorded, Related Allowance	0	0
Impaired financing receivables	25	113
Impaired Financing Receivable, Unpaid Principal Balance, Total	32	190
Impaired Financing Receivable, Related Allowance, Total	1	2
Without a related allowance recorded, Average Recorded Investment	35	117
Without a related allowance recorded, Interest Income Recognized	1	1
With a related allowance recorded, Average Recorded Investment	2	2
With a related allowance recorded, Interest Income Recognized	0	0
Impaired Financing Receivable, Average Recorded Investment, Total	37	119
Impaired Financing Receivable, Interest Income Recognized, Total	$ 1	$ 1

Impaired financing receivable with no related allowance.

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No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

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- Definition

Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
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-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524

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- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

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- Definition

Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

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Amount of average investment of impaired financing receivables for which there is no related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

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Amount of interest income, recognized on accrual basis, on financing receivables that are recognized as impaired, for which there is no related allowance for credit losses.

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Amount of interest income, recognized on accrual basis, on financing receivables, for which there is a related allowance for credit losses and are recognized as impaired.

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