Loans and Leases - Summary of Non-Performing Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructurings	$ 46,975	$ 45,500
Non-Performing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	74,828	49,897
Troubled debt restructurings	20,638	22,028
Total non-performing loans	95,466	71,925
Other real estate owned (OREO)	40,523	38,918
Total non-performing assets	$ 135,989	$ 110,843
Non-performing loans / total loans and leases	0.65%	0.59%
Non-performing loans + OREO / total loans and leases + OREO	0.92%	0.91%
Non-performing assets / of total assets	0.63%	0.63%