Loans and Leases - Summary of Non-Performing Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructurings	$ 49,914	$ 45,500
Non-Performing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	63,036	49,897
Troubled debt restructurings	21,453	22,028
Total non-performing loans	84,489	71,925
Other real estate owned (OREO)	50,526	38,918
Total non-performing assets	$ 135,015	$ 110,843
Non-performing loans as a percent of total loans and leases	0.60%	0.59%
Non-performing loans + OREO as a percent of total loans and leases + OREO	0.95%	0.91%
Non-performing assets as a percent of total assets	0.66%	0.63%