Loans and Leases - Summary of Payment Status of Originated TDRs (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Financing Receivable, Modifications [Line Items]
Troubled debt restructurings ("TDRs")	$ 46,975	$ 45,500
Performing [Member]
Financing Receivable, Modifications [Line Items]
Troubled debt restructurings ("TDRs")	17,030	15,165
Non-Performing [Member]
Financing Receivable, Modifications [Line Items]
Troubled debt restructurings ("TDRs")	20,638	22,028
Non-Accrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled debt restructurings ("TDRs")	$ 9,307	$ 8,307