Allowance For Loan Loss - Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Financing Receivable, Impaired [Line Items]
Total recorded investment in impaired loans	$ 29,663		$ 29,663		$ 31,796
Total accruing impaired loans	17,300		17,300		22,400
Impaired non-accrual loans	12,400		12,400		9,400
Unpaid contractual principal balance	32,092		32,092		34,764
Recorded investment with no allowance	23,652		23,652		25,659
Recorded investment with allowance	6,011		6,011		6,137
Related allowance	2,226		2,226		2,621
Average recorded investment	30,075	$ 28,511	29,610	$ 24,888
Interest income recognized	208	214	615	458
Additional funding commitments on impaired loans	414		414
Commercial real estate
Financing Receivable, Impaired [Line Items]
Total recorded investment in impaired loans	15,133		15,133		14,261
Unpaid contractual principal balance	16,739		16,739		16,010
Recorded investment with no allowance	12,876		12,876		12,444
Recorded investment with allowance	2,257		2,257		1,817
Related allowance	386		386		370
Average recorded investment	15,401	14,828	14,394	12,399
Interest income recognized	92	107	271	214
Commercial and industrial
Financing Receivable, Impaired [Line Items]
Total recorded investment in impaired loans	12,098		12,098		13,372
Unpaid contractual principal balance	12,591		12,591		14,291
Recorded investment with no allowance	8,406		8,406		9,366
Recorded investment with allowance	3,692		3,692		4,006
Related allowance	1,778		1,778		2,222
Average recorded investment	12,264	9,889	12,503	8,801
Interest income recognized	94	69	275	134
Commercial construction
Financing Receivable, Impaired [Line Items]
Total recorded investment in impaired loans	1,615		1,615		3,364
Unpaid contractual principal balance	1,665		1,665		3,408
Recorded investment with no allowance	1,615		1,615		3,051
Recorded investment with allowance	0		0		313
Related allowance	0		0		28
Average recorded investment	1,617	3,113	1,884	3,059
Interest income recognized	21	39	70	113
Residential
Financing Receivable, Impaired [Line Items]
Total recorded investment in impaired loans	403		403		289
Unpaid contractual principal balance	515		515		388
Recorded investment with no allowance	403		403		289
Recorded investment with allowance	0		0		0
Related allowance	0		0		0
Average recorded investment	315	300	293	304
Interest income recognized	0	0	0	0
Home Equity
Financing Receivable, Impaired [Line Items]
Total recorded investment in impaired loans	378		378		509
Unpaid contractual principal balance	545		545		665
Recorded investment with no allowance	352		352		509
Recorded investment with allowance	26		26		0
Related allowance	26		26		0
Average recorded investment	451	368	518	307
Interest income recognized	1	(2)	(1)	(4)
Consumer
Financing Receivable, Impaired [Line Items]
Total recorded investment in impaired loans	36		36		1
Unpaid contractual principal balance	37		37		2
Recorded investment with no allowance	0		0		0
Recorded investment with allowance	36		36		1
Related allowance	36		36		$ 1
Average recorded investment	27	13	18	18
Interest income recognized	$ 0	$ 1	$ 0	$ 1

Financing Receivable, Recorded Investment, Impaired and Nonaccrual Status

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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
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-Publisher FASB
-Name Accounting Standards Codification
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