Loans - Change in the Balances of the ALLL (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Allowance for loan losses:
Balance, beginning of period	$ 21,840	$ 17,896
Provision (credit) charged to expense	1,461	1,285
Losses charged off	(498)	(429)
Recoveries	54	89
Balance, end of period	22,857	18,841
Commercial and industrial
Allowance for loan losses:
Balance, beginning of period	1,521	1,384
Provision (credit) charged to expense	346	79
Losses charged off	(197)	(112)
Recoveries	0	0
Balance, end of period	1,670	1,351
Owner-occupied commercial real estate
Allowance for loan losses:
Balance, beginning of period	561	783
Provision (credit) charged to expense	84	(38)
Losses charged off	0	0
Recoveries	0	0
Balance, end of period	645	745
Investor commercial real estate
Allowance for loan losses:
Balance, beginning of period	109	61
Provision (credit) charged to expense	19	42
Losses charged off	0	0
Recoveries	0	0
Balance, end of period	128	103
Construction
Allowance for loan losses:
Balance, beginning of period	380	251
Provision (credit) charged to expense	80	16
Losses charged off	0	0
Recoveries	0	0
Balance, end of period	460	267
Single tenant lease financing
Allowance for loan losses:
Balance, beginning of period	11,175	8,827
Provision (credit) charged to expense	(420)	541
Losses charged off	0	0
Recoveries	0	0
Balance, end of period	10,755	9,368
Public finance
Allowance for loan losses:
Balance, beginning of period	1,580	1,670
Provision (credit) charged to expense	(97)	(20)
Losses charged off	0	0
Recoveries	0	0
Balance, end of period	1,483	1,650
Healthcare finance
Allowance for loan losses:
Balance, beginning of period	3,247	1,264
Provision (credit) charged to expense	1,071	467
Losses charged off	0	0
Recoveries	0	0
Balance, end of period	4,318	1,731
Small business lending
Allowance for loan losses:
Balance, beginning of period	54	203
Provision (credit) charged to expense	203	(8)
Losses charged off	0	0
Recoveries	8	0
Balance, end of period	265	195
Residential mortgage
Allowance for loan losses:
Balance, beginning of period	657	1,079
Provision (credit) charged to expense	(143)	(36)
Losses charged off	(15)	0
Recoveries	1	1
Balance, end of period	500	1,044
Home equity
Allowance for loan losses:
Balance, beginning of period	46	53
Provision (credit) charged to expense	5	(6)
Losses charged off	0	0
Recoveries	2	2
Balance, end of period	53	49
Other consumer
Allowance for loan losses:
Balance, beginning of period	2,510	2,321
Provision (credit) charged to expense	313	248
Losses charged off	(286)	(317)
Recoveries	43	86
Balance, end of period	$ 2,580	$ 2,338

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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- Definition

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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Amount of expense related to estimated loss from loan and lease transactions.

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