Premises and Equipment (Premises and Equipment) (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment [Line Items]
Land	$ 105,004	$ 103,359
Buildings	238,782	248,232
Furniture and equipment	201,843	196,681
Leasehold improvements	59,489	56,531
Construction in progress	3,503	4,269
Premises and equipment, Gross	608,621	609,072
Less accumulated depreciation and amortization	(292,687)	(290,030)
Total premises and equipment, net	$ 315,934	$ 319,042