Loans and Leases (Investments in TDRs, Segregated by Risk Rating Exposure) (Detail) - USD ($) $ in Thousands		Jun. 30, 2016	Dec. 31, 2015
Financing Receivable, Modifications [Line Items]
Total recorded investment of TDRs	[1]	$ 247,498	$ 272,690
Commerial, Commercial Real Estate, Equipment Financing TDR's [Member]
Financing Receivable, Modifications [Line Items]
Total recorded investment of TDRs		71,958	89,818
Commerial, Commercial Real Estate, Equipment Financing TDR's [Member] | (1) - (6) Pass [Member]
Financing Receivable, Modifications [Line Items]
Total recorded investment of TDRs		11,813	12,970
Commerial, Commercial Real Estate, Equipment Financing TDR's [Member] | (7) Special Mention [Member]
Financing Receivable, Modifications [Line Items]
Total recorded investment of TDRs		2,927	2,999
Commerial, Commercial Real Estate, Equipment Financing TDR's [Member] | (8) Substandard [Member]
Financing Receivable, Modifications [Line Items]
Total recorded investment of TDRs		57,043	72,132
Commerial, Commercial Real Estate, Equipment Financing TDR's [Member] | (9) Doubtful [Member]
Financing Receivable, Modifications [Line Items]
Total recorded investment of TDRs		$ 175	$ 1,717

[1] Total recorded investment of TDRs excludes $1.0 million and $1.1 million of accrued interest receivable at June 30, 2016 and December 31, 2015, respectively.