Revenue from contracts with customers - Revenue streams (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Service charges on deposit accounts
Revenue From Contract With Customer Excluding Assessed Tax	$ 39,617	$ 37,102	$ 78,308	$ 73,557
BPPR
Revenue From Contract With Customer Excluding Assessed Tax	94,083	82,770	175,851	162,080
BPPR | Service charges on deposit accounts
Revenue From Contract With Customer Excluding Assessed Tax	36,035	33,776	71,099	66,955
BPPR | Debit card fees
Revenue From Contract With Customer Excluding Assessed Tax	11,752	11,425	22,651	22,820
BPPR | Insurance fees, excluding reinsurance
Revenue From Contract With Customer Excluding Assessed Tax	13,420	8,650	20,865	15,887
BPPR | Credit card fees excluding late fees and membership fees
Revenue From Contract With Customer Excluding Assessed Tax	21,392	18,681	39,678	35,484
BPPR | Sale and administration of investment products
Revenue From Contract With Customer Excluding Assessed Tax	5,732	5,020	10,991	10,375
BPPR | Trust fees
Revenue From Contract With Customer Excluding Assessed Tax	5,752	5,218	10,567	10,559
Popular U.S.
Revenue From Contract With Customer Excluding Assessed Tax	4,918	4,655	9,802	9,036
Popular U.S. | Service charges on deposit accounts
Revenue From Contract With Customer Excluding Assessed Tax	3,582	3,326	7,209	6,602
Popular U.S. | Debit card fees
Revenue From Contract With Customer Excluding Assessed Tax	282	259	553	502
Popular U.S. | Insurance fees, excluding reinsurance
Revenue From Contract With Customer Excluding Assessed Tax	831	833	1,601	1,455
Popular U.S. | Credit card fees excluding late fees and membership fees
Revenue From Contract With Customer Excluding Assessed Tax	223	237	439	477
Popular U.S. | Sale and administration of investment products
Revenue From Contract With Customer Excluding Assessed Tax	0	0	0	0
Popular U.S. | Trust fees
Revenue From Contract With Customer Excluding Assessed Tax	$ 0	$ 0	$ 0	$ 0