Loans - Non-covered loans HIP in past due status, non-performing status and accruing loans past-due 90 days or more by loan class (Parenthetical) (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable
Unearned Income	$ 173,266	$ 155,824
Loans held-for-sale, at lower of cost or fair value	56,370	51,422
Loans held-in-portfolio, net of unearned income	27,007,975	26,507,889
Non Covered Loans [Member]
Accounts, Notes, Loans and Financing Receivable
Pledged Financial Instruments, Not Separately Reported, Loans Receivable Pledged as Collateral	6,700,000	6,900,000
Loans-held-in portfolio served as collateral to secure credit facilities authorized with the FHLB	4,600,000	4,800,000
Loans held-in-portfolio, net of unearned income	27,007,975	26,507,889
FRB Discount Window \| Non Covered Loans [Member]
Accounts, Notes, Loans and Financing Receivable
Loans served as collateral to secure debt obligations	2,100,000	2,100,000
PUERTO RICO
Accounts, Notes, Loans and Financing Receivable
Loans held-in-portfolio, net of unearned income	19,932,582	19,883,472
PUERTO RICO \| Non Covered Loans [Member]
Accounts, Notes, Loans and Financing Receivable
Loans held-in-portfolio, net of unearned income	19,932,582	19,883,472
Popular U.S.
Accounts, Notes, Loans and Financing Receivable
Loans held-in-portfolio, net of unearned income	7,075,393	6,624,417
Popular U.S. \| Non Covered Loans [Member]
Accounts, Notes, Loans and Financing Receivable
Loans held-in-portfolio, net of unearned income	7,075,393	6,624,417
ASC Subtopic 310-30 \| Non Covered Loans [Member]
Accounts, Notes, Loans and Financing Receivable
Loans held-in-portfolio, net of unearned income	189,000	216,000
ASC Subtopic 310-30 \| PUERTO RICO \| Non Covered Loans [Member]
Accounts, Notes, Loans and Financing Receivable
Loans held-in-portfolio, net of unearned income	141,000	143,000
ASC Subtopic 310-30 \| Popular U.S. \| Non Covered Loans [Member]
Accounts, Notes, Loans and Financing Receivable
Loans held-in-portfolio, net of unearned income	$ 48,000	$ 73,000

Reflects principally the unearned financing income associated with finance lease receivables

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- Definition

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+ References

No definition available.

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

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- Definition

Amount, after allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

+ References

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- Definition

The sum of the carrying amounts, as of the date of the latest financial statement presented, of loans receivable which are owned but transferred to serve as collateral for the payment of related debt obligations, primarily secured borrowings and repurchase agreements, and for which the transferees are not permitted to sell or re-pledge them to an unrelated party.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

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- Definition

The carrying amount, as of the date of the latest financial statement presented, of loans receivable which are owned but transferred to serve as collateral for the payment of FHLB debt obligations, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

+ References

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- Definition

The carrying amount, as of the date of the latest financial statement presented, of loans receivable which are owned but transferred to serve as collateral for the payment of other debt obligations, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

+ References

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