Other services fees by major categories (Detail) - Entity [Domain] - Segment, Continuing Operations [Member] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Component of Operating Other Cost and Expense [Line Items]
Debit card fees	$ 11,995	$ 11,000	$ 23,120	$ 21,544
Insurance Commissions And Fees	13,606	12,406	25,647	24,125
Fees And Commissions Credit Cards	17,611	16,985	33,760	33,068
Asset Management Fees	6,601	7,456	12,531	13,913
Fees And Commissions Fiduciary And Trust Activities	4,914	4,566	9,516	9,029
Processing fees	0	0	0	0
Other fees	4,694	4,055	8,473	7,607
Total other services fees	$ 59,421	$ 56,468	$ 113,047	$ 109,286