Loans and Other Real Estate - Activity in the Allowance for Loan and Lease Losses by Portfolio Segment (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 40,003	$ 37,688
Charge-offs	(483)	(516)
Recoveries	141	299
Provision	9,223	508
Ending Balance	48,884	37,979
Commercial, secured by real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	28,950	27,881
Charge-offs	(169)	(187)
Recoveries	26	115
Provision	5,986	(294)
Ending Balance	34,793	27,515
Commercial, industrial and other
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	3,289	1,742
Charge-offs	0	(147)
Recoveries	30	97
Provision	2,170	900
Ending Balance	5,489	2,592
Equipment finance
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	957	987
Charge-offs	(84)	(87)
Recoveries	14	2
Provision	370	45
Ending Balance	1,257	947
Real estate - residential mortgage
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	1,725	1,566
Charge-offs	(116)	(50)
Recoveries	20	9
Provision	(29)	39
Ending Balance	1,600	1,564
Real estate - construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	2,672	3,015
Charge-offs	0	0
Recoveries	32	5
Provision	640	(133)
Ending Balance	3,344	2,887
Home equity and consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	2,410	2,497
Charge-offs	(114)	(45)
Recoveries	19	71
Provision	86	(49)
Ending Balance	$ 2,401	$ 2,474

Provision for (Recovery of) Loan and Lease Losses

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- Definition

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.

+ References

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- Definition

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

+ 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
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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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
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-SubTopic 210
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