Note Guarantees (Changes in the Corporation's liability of estimated losses associated with customary respresentations and warranties related to loans sold by BPPR) (Detail) - Indemnification Guarantee - Banco Popular de Puerto Rico - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Guarantor Obligations [Line Items]
Balance as of beginning of period	$ 11,742	$ 10,936
Provision (reversal) for representations and warranties	(152)	(399)
Net charge-offs	(172)	0
Balance as of end of period	$ 11,418	$ 10,537