Note Borrowings (Notes payable) (Parenthetical) (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Junior subordinated debt
Debt Instrument
Senior Debt Maturity Year	2033
Notes Payable Maturity Year Range Start	2034
Debt issuance costs line of credit arrangements net	$ 416
Minimum \| Junior subordinated debt
Debt Instrument
Interest Rate Percentage	6.125%
Maximum \| Junior subordinated debt
Debt Instrument
Interest Rate Percentage	6.70%
Advances with FHLB with maturities ranging from 2019 Through 2029
Debt Instrument
Notes Payable Maturity Year Range Start	2019
Notes Payable Maturity Year Range End	2029
Debt Instrument Frequency Of Periodic Payment	monthly
Advances with FHLB with maturities ranging from 2019 Through 2029 \| Minimum
Debt Instrument
Advances with the FHLB, interest rate	0.95%
Advances with FHLB with maturities ranging from 2019 Through 2029 \| Maximum
Debt Instrument
Advances with the FHLB, interest rate	4.19%
Floating rate over the 3 month LIBOR with maturities on 2019
Debt Instrument
Advances with the FHLB, interest rate	0.24%
Notes Payable Maturity Year Range End	2019
Debt Instrument Frequency Of Periodic Payment	Quarterly
Fixed Rate with maturities on 2023 paying interest semiannually \| Unsecured senior debt
Debt Instrument
Interest Rate Percentage	6.125%
Senior Debt Maturity Year	2023
Debt issuance costs line of credit arrangements net	$ 5,644
Debt Instrument Frequency Of Periodic Payment	Semi-annually

Latest year the outstanding debt instruments are required to be repaid.

No definition available.

Name:	bpop_NotesPayableMaturityYearRangeEnd
Namespace Prefix:	bpop_
Data Type:	xbrli:gYearItemType
Balance Type:	na
Period Type:	duration

- Definition

Earliest year the outstanding debt instruments are required to be repaid.

+ References

No definition available.

+ Details

Name:	bpop_NotesPayableMaturityYearRangeStart
Namespace Prefix:	bpop_
Data Type:	xbrli:gYearItemType
Balance Type:	na
Period Type:	duration

- Definition

Maturity year the outstanding debt instruments are required to be repaid.

+ References

No definition available.

+ Details

Name:	bpop_SeniorDebtMaturityYear
Namespace Prefix:	bpop_
Data Type:	xbrli:gYearItemType
Balance Type:	na
Period Type:	duration

- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

+ Details

Name:	us-gaap_DebtInstrumentFrequencyOfPeriodicPayment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt issuance costs related to line of credit arrangements. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section S45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=68176171&loc=SL68176184-208336

+ Details

Name:	us-gaap_DebtIssuanceCostsLineOfCreditArrangementsNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

States the interest rate applicable to Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

+ Details

Name:	us-gaap_FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresInterestRateAtPeriodEnd
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_JuniorSubordinatedDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=bpop_FixedRateAdvancesDue2019To2029Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=bpop_FloatingRateOverTheThreeMonthLIBORWithMaturitiesOn2019Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=bpop_FixedRateWithMaturitiesOn2023Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_UnsecuredDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: