Note Goodwill and other intangible assets (Gross amount of goodwill and accumulated impairment losses by reportable segment and corporate group) (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2016
Goodwill [Line Items]
Goodwill Gross	$ 795,506	$ 795,506		$ 795,506
Goodwill Impaired Accumulated Impairment Loss	168,212	168,212		168,212
Goodwill (net amounts)	627,294	627,294	$ 627,294	627,294
Banco Popular de Puerto Rico
Goodwill [Line Items]
Goodwill Gross	280,221	280,221		280,221
Goodwill Impaired Accumulated Impairment Loss	3,801	3,801		3,801
Goodwill (net amounts)	276,420	276,420	276,420	276,420
Popular Bank
Goodwill [Line Items]
Goodwill Gross	515,285	515,285		515,285
Goodwill Impaired Accumulated Impairment Loss	164,411	164,411		164,411
Goodwill (net amounts)	$ 350,874	$ 350,874	$ 350,874	$ 350,874

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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