Segment Reporting - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2018
Popular U.S.
Segment Reporting Information
Intercompany billings	$ 3.3	$ 9.5
Banco Popular de Puerto Rico
Segment Reporting Information
Intercompany billings	$ 21.8	$ 59.3

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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