Guarantees - Changes from customary respresentations and warranties related to loans sold by BPPR (Details) - Indemnification Guarantee - Banco Popular de Puerto Rico - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Guarantor Obligations [Line Items]
Balance as of beginning of period	$ 2,078	$ 3,122	$ 2,297	$ 3,212
Provision (reversal) for representations and warranties	(79)	(125)	(298)	(215)
Balance as of end of period	$ 1,999	$ 2,997	$ 1,999	$ 2,997