XML 69 R58.htm IDEA: XBRL DOCUMENT
v3.10.0.1

BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Detail) | 9 Months Ended
--- | ---
Sep. 30, 2018 USD ($)
Disclosure Basisof Presentationand Significant Accounting Policies Additional Information [Abstract] |
Callable Debt Securities Held At Premium | $ 4,100,000
Callable Debt Securities Unamortized Premium | 13,000
ASU 2016-02 [Member] |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification | $ 100,000,000
ASU 2016-02 [Member] | Total Assets [Member] |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |
New Accounting Pronouncement Or Change In Accounting Principle Effect Of Adoption Percentage | 1.00%

X
- Definition Amount of callable debt securities held at a premium. + References No definition available. + Details
Name: | fbp_CallableDebtSecuritiesHeldAtPremium
Namespace Prefix: | fbp_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount, after accumulated amortization, of debt premium on callable securities. + References No definition available. + Details
Name: | fbp_CallableDebtSecuritiesUnamortizedPremium
Namespace Prefix: | fbp_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Disclosure - BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Additional Information [Abstract] + References No definition available. + Details
Name: | fbp_DisclosureBasisofPresentationandSignificantAccountingPoliciesAdditionalInformationAbstract
Namespace Prefix: | fbp_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the percentage of the effect of adopting the new accounting standard or change in accounting principle expected by the entity to have a significant effect on the entity's financial statements. + References No definition available. + Details
Name: | fbp_NewAccountingPronouncementOrChangeInAccountingPrincipleEffectOfAdoptionPercentage
Namespace Prefix: | fbp_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the quantification of the effect of adopting the new accounting standard or change in accounting principle expected by the entity to have a significant effect on the entity's financial statements. + References No definition available. + Details
Name: | us-gaap_NewAccountingPronouncementOrChangeInAccountingPrincipleEffectOfAdoptionQuantification
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- 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_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=us-gaap_AccountingStandardsUpdate201602Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_AssetsTotalMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |