Loans - Change in the Balances of the ALLL (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Allowance for loan losses:
Balance, beginning of period	$ 22,857	$ 18,841	$ 21,840	$ 17,896
Provision (credit) charged to expense	2,491	1,389	3,952	2,674
Losses charged off	(1,016)	(337)	(1,514)	(766)
Recoveries	133	83	187	172
Balance, end of period	24,465	19,976	24,465	19,976
Commercial and industrial
Allowance for loan losses:
Balance, beginning of period	1,670	1,351	1,521	1,384
Provision (credit) charged to expense	(141)	444	205	523
Losses charged off	(57)	0	(254)	(112)
Recoveries	5	0	5	0
Balance, end of period	1,477	1,795	1,477	1,795
Owner-occupied commercial real estate
Allowance for loan losses:
Balance, beginning of period	645	847	561	891
Provision (credit) charged to expense	201	(223)	285	(267)
Losses charged off	0	0	0	0
Recoveries	0	0	0	0
Balance, end of period	846	624	846	624
Investor commercial real estate
Allowance for loan losses:
Balance, beginning of period	128	103	109	61
Provision (credit) charged to expense	2	66	21	108
Losses charged off	0	0	0	0
Recoveries	0	0	0	0
Balance, end of period	130	169	130	169
Construction
Allowance for loan losses:
Balance, beginning of period	460	267	380	251
Provision (credit) charged to expense	261	35	341	51
Losses charged off	0	0	0	0
Recoveries	0	0	0	0
Balance, end of period	721	302	721	302
Single tenant lease financing
Allowance for loan losses:
Balance, beginning of period	10,755	9,368	11,175	8,827
Provision (credit) charged to expense	563	293	143	834
Losses charged off	0	0	0	0
Recoveries	0	0	0	0
Balance, end of period	11,318	9,661	11,318	9,661
Public finance
Allowance for loan losses:
Balance, beginning of period	1,483	1,650	1,580	1,670
Provision (credit) charged to expense	59	113	(38)	93
Losses charged off	0	0	0	0
Recoveries	0	0	0	0
Balance, end of period	1,542	1,763	1,542	1,763
Healthcare finance
Allowance for loan losses:
Balance, beginning of period	4,318	1,731	3,247	1,264
Provision (credit) charged to expense	1,187	562	2,258	1,029
Losses charged off	(743)	0	(743)	0
Recoveries	0	0	0	0
Balance, end of period	4,762	2,293	4,762	2,293
Small business lending
Allowance for loan losses:
Balance, beginning of period	265	93	54	95
Provision (credit) charged to expense	(20)	36	183	34
Losses charged off	0	0	0	0
Recoveries	6	0	14	0
Balance, end of period	251	129	251	129
Residential mortgage
Allowance for loan losses:
Balance, beginning of period	500	1,044	657	1,079
Provision (credit) charged to expense	36	(383)	(107)	(419)
Losses charged off	0	0	(15)	0
Recoveries	3	1	4	2
Balance, end of period	539	662	539	662
Home equity
Allowance for loan losses:
Balance, beginning of period	53	49	46	53
Provision (credit) charged to expense	(4)	(5)	0	(11)
Losses charged off	0	0	0	0
Recoveries	2	4	5	6
Balance, end of period	51	48	51	48
Other consumer
Allowance for loan losses:
Balance, beginning of period	2,580	2,338	2,510	2,321
Provision (credit) charged to expense	347	451	661	699
Losses charged off	(216)	(337)	(502)	(654)
Recoveries	117	78	159	164
Balance, end of period	$ 2,828	$ 2,530	$ 2,828	$ 2,530

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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