Note Subsequent events- Additional Information (Detail) - Subsequent Event - USD ($) $ in Thousands	Aug. 06, 2018	Aug. 01, 2018
Subsequent Events [Line Items]
Subsequent Events Date		Aug. 01, 2018
Business Acquisition Name Of Acquired Entity		Wells Fargo & Company's auto finance business in Puerto Rico
BanPonce Trust I \| PNA Holding Co.
Subsequent Events [Line Items]
Subsequent Events Date	Aug. 06, 2018
Capital securities	$ 52,865
Debt Redemption Price Description	The redemption price of each security will be equal to 100% of the liquidation amount of the securities plus accumulated and unpaid distributions up to and excluding the redemption date
Debt Redemption Price Percent Of Principal Amount	100.00%
Trust Preferred Securities Liquidation Amount Per Security	$ 1
Debt Instrument Interest Rate Stated Percentage	8.327%
Banco Popular de Puerto Rico \| Auto
Subsequent Events [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Financial Assets		$ 1,600,000
Loans In Servicing Agreement Retained By Acquired Entity		385,000
Banco Popular de Puerto Rico \| Commercial Loans
Subsequent Events [Line Items]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Financial Assets		$ 360,000

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Debt Redemption Price Percent Of Principal Amount

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Loans retained by acquired entity and for which the acquired entity and the acquirer entered into a servicing agreement

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A preferred undivided beneficial interest in assets of the Issuer Trust, including the rights to receive distribution and liquidation distribution to the extent provided.

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Liquidation Amount Per Security.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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The amount of financial assets (as defined) recognized as of the acquisition date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=84160947&loc=d3e2207-128464

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Contractual interest rate for funds borrowed, under the debt agreement.

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-SubTopic 10
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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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Date the event occurred after the balance sheet date but before financial statements are issues or available to be issued, in CCYY-MM-DD format.

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