Allowance For Credit Losses for Loans - Prior Period Allowance for Loan Losses (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($)
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 33,614
Provision for credit losses	6,147
Recoveries	120
Less: Charge offs	117
Ending balance	39,764
Allocated to loans individually evaluated for impairment	2,448
Allocated to loans collectively evaluated for impairment	37,316
Commercial real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	18,338
Provision for credit losses	2,523
Recoveries	0
Less: Charge offs	0
Ending balance	20,861
Allocated to loans individually evaluated for impairment	29
Allocated to loans collectively evaluated for impairment	20,832
Commercial and industrial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	9,129
Provision for credit losses	1,104
Recoveries	107
Less: Charge offs	105
Ending balance	10,235
Allocated to loans individually evaluated for impairment	908
Allocated to loans collectively evaluated for impairment	9,327
Commercial construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	4,149
Provision for credit losses	2,012
Recoveries	0
Less: Charge offs	0
Ending balance	6,161
Allocated to loans individually evaluated for impairment	1,473
Allocated to loans collectively evaluated for impairment	4,688
Residential mortgages
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,195
Provision for credit losses	403
Recoveries	0
Less: Charge offs	0
Ending balance	1,598
Allocated to loans individually evaluated for impairment	0
Allocated to loans collectively evaluated for impairment	1,598
Home equity loans and lines
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	536
Provision for credit losses	97
Recoveries	3
Less: Charge offs	0
Ending balance	636
Allocated to loans individually evaluated for impairment	0
Allocated to loans collectively evaluated for impairment	636
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	267
Provision for credit losses	8
Recoveries	10
Less: Charge offs	12
Ending balance	273
Allocated to loans individually evaluated for impairment	38
Allocated to loans collectively evaluated for impairment	$ 235

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

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
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- Definition

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

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-Publisher FASB
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