Loans, Leases and Other Real Estate - Composition of Company`s Loan and Lease Portfolio (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	$ 4,332,238	$ 4,156,680
Less: deferred fees	(4,120)	(3,960)
Loans and leases, net of deferred fees	4,328,118	4,152,720
Commercial, secured by real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	2,984,430	2,831,184
Commercial, industrial and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	334,241	340,400
Leases
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	82,881	75,039
Real estate - residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	315,135	322,880
Real estate - construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	297,516	264,908
Home equity and consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	$ 318,035	$ 322,269

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 20
-Section 50
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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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