Allowance For Loan Loss - Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Financing Receivable, Impaired [Line Items]
Total recorded investment in impaired loans	$ 31,069		$ 31,069		$ 31,530
Total accruing impaired loans	19,100		19,100		19,700
Impaired non-accrual loans	12,000		12,000		11,800
Unpaid contractual principal balance	32,845		32,845		33,153
Recorded investment with no allowance	26,815		26,815		26,423
Recorded investment with allowance	4,254		4,254		5,107
Related allowance	2,349		2,349		2,224
Average recorded investment	31,036	$ 27,992	30,953	$ 27,556
Interest income recognized	259	208	520	400
Commercial real estate
Financing Receivable, Impaired [Line Items]
Total recorded investment in impaired loans	16,906		16,906		16,318
Unpaid contractual principal balance	17,800		17,800		17,140
Recorded investment with no allowance	16,739		16,739		15,948
Recorded investment with allowance	167		167		370
Related allowance	5		5		55
Average recorded investment	16,425	13,506	16,114	13,611
Interest income recognized	122	95	242	189
Commercial and industrial
Financing Receivable, Impaired [Line Items]
Total recorded investment in impaired loans	11,042		11,042		12,053
Unpaid contractual principal balance	11,575		11,575		12,538
Recorded investment with no allowance	7,403		7,403		7,752
Recorded investment with allowance	3,639		3,639		4,301
Related allowance	2,307		2,307		2,140
Average recorded investment	11,474	11,601	11,696	11,124
Interest income recognized	94	89	209	166
Commercial construction
Financing Receivable, Impaired [Line Items]
Total recorded investment in impaired loans	1,723		1,723		1,736
Unpaid contractual principal balance	1,800		1,800		1,804
Recorded investment with no allowance	1,723		1,723		1,736
Recorded investment with allowance	0		0		0
Related allowance	0		0		0
Average recorded investment	1,738	1,676	1,736	1,656
Interest income recognized	27	23	52	45
Residential mortgages
Financing Receivable, Impaired [Line Items]
Total recorded investment in impaired loans	934		934		893
Unpaid contractual principal balance	1,024		1,024		970
Recorded investment with no allowance	518		518		473
Recorded investment with allowance	416		416		420
Related allowance	5		5		13
Average recorded investment	939	644	914	629
Interest income recognized	17	1	18	0
Home equity loans and lines
Financing Receivable, Impaired [Line Items]
Total recorded investment in impaired loans	432		432		514
Unpaid contractual principal balance	614		614		685
Recorded investment with no allowance	432		432		514
Recorded investment with allowance	0		0		0
Related allowance	0		0		0
Average recorded investment	436	499	472	487
Interest income recognized	0	0	0	0
Consumer
Financing Receivable, Impaired [Line Items]
Total recorded investment in impaired loans	32		32		16
Unpaid contractual principal balance	32		32		16
Recorded investment with no allowance	0		0		0
Recorded investment with allowance	32		32		16
Related allowance	32		32		$ 16
Average recorded investment	24	66	21	49
Interest income recognized	$ (1)	$ 0	$ (1)	$ 0

Financing Receivable, Recorded Investment, Impaired and Nonaccrual Status

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- Definition

Reflects the carrying amount of impaired loans on which interest is continuing to be earned or accrued.

+ References

No definition available.

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
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-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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Amount of allowance for credit losses related to recorded investment.

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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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