Segment reporting - Selected Balance Sheet information (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025
Segment Reporting Information [Line Items]
Assets	$ 76,131,018	$ 75,348,267	$ 74,038,606
Deposits	67,611,316	66,190,093
Puerto Rico
Segment Reporting Information [Line Items]
Assets	58,510,727	57,955,465
Loans	25,884,571	25,853,231
Deposits	53,602,880	52,451,498
Popular U.S.
Segment Reporting Information [Line Items]
Assets	16,278,568	16,101,705
Loans	12,894,276	12,966,468
Deposits	12,185,414	11,987,581
Other
Segment Reporting Information [Line Items]
Assets	1,341,723	1,291,097
Loans	516,458	517,817
Deposits	$ 1,823,022	$ 1,751,014

Amount of asset recognized for present right to economic benefit.

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+ Details