Note Segment reporting (Selected Balance Sheet information) (Detail) - USD ($) $ in Thousands		Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016
Segment Reporting Information [Line Items]
Total assets		$ 40,259,282	$ 38,661,609	$ 36,147,009
Deposits		32,212,579	30,496,224
PUERTO RICO
Segment Reporting Information [Line Items]
Total assets		30,185,470	28,813,289
Loans		16,619,906	16,880,868
Deposits		24,722,769	23,185,551
UNITED STATES
Segment Reporting Information [Line Items]
Total assets		9,159,712	8,928,475
Loans		6,003,805	5,799,562
Deposits		6,445,544	6,266,473
Other
Segment Reporting Information [Line Items]
Total assets		914,100	919,845
Loans		748,299	755,017
Deposits	[1]	$ 1,044,266	$ 1,044,200

[1] Represents deposits from BPPR operations located in the US and British Virgin Islands.