Note Guarantees (Other Guarantees) - Additional Information (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Guarantor Obligations [Line Items]
Funds Advanced To Investors Under Servicing Agreements	$ 110,076	$ 107,299
Debt Securities Payable | Popular, Inc. Holding Co.
Guarantor Obligations [Line Items]
Guarantees, unamortized balance of the obligations	149	149
Financial Standby Letter Of Credit
Guarantor Obligations [Line Items]
Guarantees, unamortized balance of the obligations	500	300
Guarantee Type, Other | Capital securities (trust preferred securities) | Popular, Inc. Holding Co.
Guarantor Obligations [Line Items]
Guarantees, unamortized balance of the obligations	$ 427	$ 427