Note Other services fees (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Disclosure - Other Services Fees by Major Categories [Abstract]
Debit card fees	$ 10,359	$ 11,483	$ 33,478	$ 34,153
Insurance fees	13,076	15,943	39,410	42,678
Credit card fees	16,699	17,644	54,280	52,202
Sale and administration of investment products	5,496	5,542	16,377	15,798
Trust fees	4,817	4,968	14,675	14,029
Other fees	3,034	3,589	10,604	10,636
Total other services fees	$ 53,481	$ 59,169	$ 168,824	$ 169,496