Revenue from Contracts with Customers (Disaggregation by Timing of Revenue Recognition) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Wealth management revenues	$ 9,454	$ 10,013	$ 29,329	$ 29,432
Card interchange fees	983	894	2,791	2,598
Service charges on deposit accounts	885	942	2,651	2,726
Other income	419	400	1,066	1,180
Total revenues	48,664	47,342	145,363	137,241
Revenue from Contracts with Customers [Member]
Wealth management revenues	9,454	10,013	29,329	29,432
Card interchange fees	983	894	2,791	2,598
Service charges on deposit accounts	885	942	2,651	2,726
Other income	419	400	1,051	1,139
Total revenues	11,741	12,249	35,822	35,895
Transferred at Point in Time [Member] \| Revenue from Contracts with Customers [Member]
Card interchange fees	983	894	2,791	2,598
Service charges on deposit accounts	670	741	2,045	2,140
Other income	258	283	732	872
Transferred over Time [Member] \| Revenue from Contracts with Customers [Member]
Wealth management revenues	9,454	10,013	29,329	29,432
Service charges on deposit accounts	215	201	606	586
Other income	$ 161	$ 117	$ 319	$ 267

Includes amounts charged depositors for: (1) maintenance of their accounts (maintenance charges); (2) failure to maintain specified minimum balances on account; (3) exceeding the number of checks or transactions allowed to be processed in a given period; (4) checks drawn on no minimum balance deposit accounts; (5) withdrawals from nontransaction deposit accounts; (6) closing savings accounts before a specified minimum period of time has elapsed; (7) accounts which have remained inactive for extended periods of time or which have become dormant; (8) use of automated teller machines or remote service units; (9) checks drawn against insufficient funds that the bank assesses regardless of whether it decides to pay, return or hold the check; (10) issuing stop payment orders; (11) certifying checks; and (12) accumulating or disbursing funds deposited in IRAs or Keogh Plan accounts when not handled by the bank's trust department. This item does not include penalties assessed on the early withdrawal of time deposits.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13 (d))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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Amount of revenue from providing investment advisory, asset management and administrative services, including, but not limited to, distribution and shareholder services, accounting, tax, legal, regulatory filing, share registration, and shareholder correspondence activities.

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Represents the total of noninterest income derived from certain activities and assets including (for example): (1) venture capital investments; (2) bank owned life insurance; (3) foreign currency transactions; and (4) mortgage servicing rights.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Fees earned from debit card transactions.

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