Commitments and Contingencies Disclosure [Line Items]

No definition available.

Name:	bpop_CommitmentsAndContingenciesDisclosureLineItems
Namespace Prefix:	bpop_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Concentration of Risk Credit Facilities with the Puerto Rico government that is outstanding.

+ References

No definition available.

+ Details

Name:	bpop_ConcentrationOfRiskCreditFacilities
Namespace Prefix:	bpop_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Total exposure on financial instruments with the government

+ References

No definition available.

+ Details

Name:	bpop_ConcentrationRiskCreditRiskFinancialInstrumentMaximumExposure1
Namespace Prefix:	bpop_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The Corporations exposure to municipal loans and securities was concentrated in the municipalities of San Juan, Guaynabo, Carolina and Bayamon.

+ References

No definition available.

+ Details

Name:	bpop_ExposureMunicipalLoansAndSecurities
Namespace Prefix:	bpop_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount before allowance of consumer mortgage held and guaranteed by the Puerto Rico Housing Authority.

+ References

No definition available.

+ Details

Name:	bpop_LoansAndLeasesReceivableConsumerMortgageWithPrha
Namespace Prefix:	bpop_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

+ Details

Name:	us-gaap_ValuationAllowancesAndReservesBalance
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	bpop_ExposureTypeAxis=bpop_PrGovernmentDirectExposureMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	bpop_ObligationsTypeAxis=bpop_FromMunicipalitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	bpop_ExposureTypeAxis=bpop_PrGovernmentIndirectExposureMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	bpop_ObligationsTypeAxis=us-gaap_BondsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	bpop_ObligationsTypeAxis=us-gaap_CommercialRealEstateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	bpop_ObligationsTypeAxis=bpop_PassThroughSecuritiesBackedByFnmaAndGnmaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	bpop_ExposureTypeAxis=bpop_UsvigovernmentdirectexposureMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	bpop_LoansLeasesAndFinancialInstrumentsAxis=bpop_OutstandingBalanceMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_CommitmentsToExtendCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_LoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_SecuritiesInvestmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Note Commitments and contingencies (Commitments) - Additional Information (Detail) - USD ($) $ in Thousands		9 Months Ended
	Jul. 02, 2018	Sep. 30, 2018	Dec. 31, 2017
Commitments and Contingencies Disclosure [Line Items]
Exposure Municipal Loans And Securities		75.00%
PR Government Direct Exposure \| From Municipalities
Commitments and Contingencies Disclosure [Line Items]
Concentration Risk Credit Risk Financial Instrument Maximum Exposure 1	$ 23,000
PR Government Indirect Exposure
Commitments and Contingencies Disclosure [Line Items]
Concentration Of Risk Credit Facilities		$ 374,000	$ 386,000
PR Government Indirect Exposure \| PR Housing Bonds backed by second mortgage loans
Commitments and Contingencies Disclosure [Line Items]
Concentration Of Risk Credit Facilities		44,000	44,000
PR Government Indirect Exposure \| Commercial real estate
Commitments and Contingencies Disclosure [Line Items]
Concentration Of Risk Credit Facilities		24,000	25,000
PR Government Indirect Exposure \| Pass Through securities that have been economically defeased and refunded
Commitments and Contingencies Disclosure [Line Items]
Concentration Of Risk Credit Facilities		7,000	7,000
USVI Government Direct Exposure
Commitments and Contingencies Disclosure [Line Items]
Concentration Risk Credit Risk Financial Instrument Maximum Exposure 1		78,000
Outstanding Balance \| PR Government Direct Exposure
Commitments and Contingencies Disclosure [Line Items]
Concentration Of Risk Credit Facilities		457,995	483,580
Outstanding Balance \| PR Government Direct Exposure \| From Municipalities
Commitments and Contingencies Disclosure [Line Items]
Concentration Of Risk Credit Facilities		457,910
Outstanding Balance \| PR Government Indirect Exposure
Commitments and Contingencies Disclosure [Line Items]
Loans and Leases Receivable, Consumer, Mortgage with PRHA		299,000	310,000
Commitments To Extend Credit
Commitments and Contingencies Disclosure [Line Items]
Reserve of potential losses associated with unfunded loan commitments		8,000	10,000
Loans \| Outstanding Balance \| PR Government Direct Exposure
Commitments and Contingencies Disclosure [Line Items]
Concentration Of Risk Credit Facilities		413,165	434,493
Loans \| Outstanding Balance \| PR Government Direct Exposure \| From Municipalities
Commitments and Contingencies Disclosure [Line Items]
Concentration Of Risk Credit Facilities		413,165
Securities Investment \| Outstanding Balance \| PR Government Direct Exposure
Commitments and Contingencies Disclosure [Line Items]
Concentration Of Risk Credit Facilities		44,830	$ 49,045
Securities Investment \| Outstanding Balance \| PR Government Direct Exposure \| From Municipalities
Commitments and Contingencies Disclosure [Line Items]
Concentration Of Risk Credit Facilities		$ 44,745