Revenue from Contracts with Customers (Disaggregation by Timing of Revenue Recognition) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Card interchange fees	$ 961	$ 902	$ 1,808	$ 1,704
Service charges on deposit accounts	903	901	1,766	1,784
Other income	381	456	647	780
Wealth management revenues	9,602	9,942	19,875	19,419
Total revenues	49,104	46,710	96,699	89,899
Revenue from Contracts with Customers [Member]
Card interchange fees	961	902	1,808	1,704
Service charges on deposit accounts	903	901	1,766	1,784
Other income	366	442	632	739
Wealth management revenues	9,602	9,942	19,875	19,419
Total revenues	11,832	12,187	24,081	23,646
Transferred at Point in Time [Member] \| Revenue from Contracts with Customers [Member]
Card interchange fees	961	902	1,808	1,704
Service charges on deposit accounts	703	707	1,375	1,399
Other income	248	367	474	589
Transferred over Time [Member] \| Revenue from Contracts with Customers [Member]
Service charges on deposit accounts	200	194	391	385
Other income	118	75	158	150
Wealth management revenues	$ 9,602	$ 9,942	$ 19,875	$ 19,419

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.

+ References

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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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