Segment reporting - Selected Balance Sheet information (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024	Mar. 31, 2024
Segment Reporting Information [Line Items]
Assets	$ 74,038,606	$ 73,045,383	$ 70,936,939
Deposits	65,819,255	64,884,345
Puerto Rico
Segment Reporting Information [Line Items]
Assets	56,870,242	55,888,211
Loans	24,279,836	24,154,610
Deposits	52,675,896	52,099,309
Popular U.S.
Segment Reporting Information [Line Items]
Assets	15,900,462	15,890,339
Loans	12,452,697	12,431,859
Deposits	11,388,174	11,030,879
Other
Segment Reporting Information [Line Items]
Assets	1,267,902	1,266,833
Loans	526,576	526,606
Deposits	$ 1,755,186	$ 1,754,157

Amount of asset recognized for present right to economic benefit.

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+ Details