Revenue from contracts with customers - Revenue streams (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Service charges on deposit accounts
Revenue From Contract With Customer Excluding Assessed Tax	$ 39,620	$ 41,659
BPPR
Revenue From Contract With Customer Excluding Assessed Tax	93,404	87,435
BPPR | Service charges on deposit accounts
Revenue From Contract With Customer Excluding Assessed Tax	36,859	38,331
BPPR | Debit card fees
Revenue From Contract With Customer Excluding Assessed Tax	11,342	9,999
BPPR | Insurance fees, excluding reinsurance
Revenue From Contract With Customer Excluding Assessed Tax	8,238	7,688
BPPR | Credit card fees excluding late fees and membership fees
Revenue From Contract With Customer Excluding Assessed Tax	25,410	19,768
BPPR | Sale and administration of investment products
Revenue From Contract With Customer Excluding Assessed Tax	5,540	6,263
BPPR | Trust fees
Revenue From Contract With Customer Excluding Assessed Tax	6,015	5,386
Popular U.S.
Revenue From Contract With Customer Excluding Assessed Tax	3,853	4,545
Popular U.S. | Service charges on deposit accounts
Revenue From Contract With Customer Excluding Assessed Tax	2,761	3,328
Popular U.S. | Debit card fees
Revenue From Contract With Customer Excluding Assessed Tax	235	238
Popular U.S. | Insurance fees, excluding reinsurance
Revenue From Contract With Customer Excluding Assessed Tax	609	737
Popular U.S. | Credit card fees excluding late fees and membership fees
Revenue From Contract With Customer Excluding Assessed Tax	248	242
Popular U.S. | Sale and administration of investment products
Revenue From Contract With Customer Excluding Assessed Tax	0	0
Popular U.S. | Trust fees
Revenue From Contract With Customer Excluding Assessed Tax	$ 0	$ 0