Recalibration and updates of the enviromental factors adjustments.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of charge-offs of financing receivables charged against the allowance.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Historical loss period used to compute the base net loss rate in the determination for the general reserves of the allowance for loan losses.

+ References

No definition available.

+ Details

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- Definition

Recent loss trend adjustment replaces the base loss rate, when these trends are higher than the respective base loss rates, up to a determined cap. The objective of this adjustment is to include information about recent increases in loss rates in a timely and prudent manner.

+ References

No definition available.

+ Details

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- Definition

Percentage of the ALLL for our loan portfolios that utilized the recent loss trend adjustment instead of the base loss.

+ References

No definition available.

+ Details

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- 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

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

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

- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

+ Details

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

- Definition

Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

+ Details

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

- Details

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- Details

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- Details

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- Details

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Note Allowance for loan losses (Allowance for loan losses - Additional Information) (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($) loans	Dec. 31, 2017 USD ($) loans	Sep. 30, 2018 USD ($)
Financing Receivable
Recent Loss Trend Adjustment	12-months
Charge-offs	$ 352,622	$ 311,575
Loan count \| loans	527	641
Note A / B Split
Financing Receivable
Troubled debt restructurings	$ 52,500
Aggregated unpaid principal balance	82,100
Charge-offs	29,600
Recorded investment - with an Allowance	$ 105
Loan count \| loans	6
Non Covered Loans
Financing Receivable
Troubled debt restructurings	$ 1,515,889	$ 1,258,327
Aggregated unpaid principal balance	1,245,816	1,108,393
Recorded investment - with an Allowance	$ 795,308	$ 834,526
Non Covered Loans \| Banco Popular de Puerto Rico
Financing Receivable
Recent Loss Trend Adjustment Percentage	26.00%	69.00%
Non Covered Loans \| PB
Financing Receivable
Recent Loss Trend Adjustment Percentage	28.00%	3.00%
Mortgage and consumer
Financing Receivable
Historical Loss Period	18-months
Commercial and construction
Financing Receivable
Historical Loss Period	5-year
Mortgages
Financing Receivable
Charge-offs	$ 71,071	$ 83,393
Mortgages \| Non Covered Loans
Financing Receivable
Troubled debt restructurings	1,042,470	930,076
Aggregated unpaid principal balance	605,120	591,070
Recorded investment - with an Allowance	$ 416,004	$ 457,000
Loan
Financing Receivable
Change Allowance For Loan Losses Recalibration And Updates Of The Enviromental Factors Adjustments			$ 6,100
Loan \| Banco Popular de Puerto Rico
Financing Receivable
Change Allowance For Loan Losses Recalibration And Updates Of The Enviromental Factors Adjustments			5,900
Loan \| PB
Financing Receivable
Change Allowance For Loan Losses Recalibration And Updates Of The Enviromental Factors Adjustments			$ 200