Loans and Leases - Allowance for Loan and Leases Losses Activity (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance				$ 17,525				$ 17,486	$ 17,525	$ 17,486
Charge-offs									(5,835)	(3,126)
Recoveries									543	547
Provision for loan and lease losses	$ 2,362	$ 664	$ 3,137	1,030	$ 1,077	$ 1,333	$ (83)	291	7,193	2,618	$ 4,326
Balance	19,426				17,525				19,426	17,525	17,486
Commercial mortgage
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance				7,550				6,227	7,550	6,227
Charge-offs									(331)	(55)
Recoveries									16	12
Provision for loan and lease losses									332	1,366
Balance	7,567				7,550				7,567	7,550	6,227
Home equity lines and loans
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance				1,086				1,255	1,086	1,255
Charge-offs									(333)	(675)
Recoveries									2	5
Provision for loan and lease losses									248	501
Balance	1,003				1,086				1,003	1,086	1,255
Residential mortgage
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance				1,926				1,917	1,926	1,917
Charge-offs									(354)	(326)
Recoveries									56	165
Provision for loan and lease losses									185	170
Balance	1,813				1,926				1,813	1,926	1,917
Construction
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance				937				2,233	937	2,233
Charge-offs									0	0
Recoveries									2	4
Provision for loan and lease losses									546	(1,300)
Balance	1,485				937				1,485	937	2,233
Commercial and industrial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance				5,038				5,142	5,038	5,142
Charge-offs									(1,374)	(692)
Recoveries									24	25
Provision for loan and lease losses									1,773	563
Balance	5,461				5,038				5,461	5,038	5,142
Consumer
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance				246				153	246	153
Charge-offs									(311)	(154)
Recoveries									10	8
Provision for loan and lease losses									284	239
Balance	229				246				229	246	153
Leases
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance				$ 742				$ 559	742	559
Charge-offs									(3,132)	(1,224)
Recoveries									433	328
Provision for loan and lease losses									3,825	1,079
Balance	$ 1,868				$ 742				$ 1,868	$ 742	$ 559