Fair value of corporate bonds.

No definition available.

Name:	fbp_CorporateBondsFairValueDisclosure
Namespace Prefix:	fbp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value of equity securities.

+ References

No definition available.

+ Details

Name:	fbp_EquitySecuritiesFairValueDisclosure
Namespace Prefix:	fbp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value of government sponsored enterprise securities.

+ References

No definition available.

+ Details

Name:	fbp_GovernmentSponsoredEnterpriseSecuritiesFairValueDisclosure
Namespace Prefix:	fbp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value of impaired loans covered by loss sharing arrangements.

+ References

No definition available.

+ Details

Name:	fbp_ImpairedLoansCoveredFairValueDisclosure
Namespace Prefix:	fbp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value of impaired loans not covered by loss sharing arrangements.

+ References

No definition available.

+ Details

Name:	fbp_ImpairedLoansNonCoveredFairValueDisclosure
Namespace Prefix:	fbp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

fair value of other real estate covered by loss sharing agreements.

+ References

No definition available.

+ Details

Name:	fbp_OtherRealEstateCoveredFairValueDisclosure
Namespace Prefix:	fbp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value of other real estate not covered by loss sharing agreements.

+ References

No definition available.

+ Details

Name:	fbp_OtherRealEstateNonCoveredFairValueDisclosure
Namespace Prefix:	fbp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=51813488&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (aa)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=49167202&loc=d3e26610-111562

+ Details

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

- Details

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

- Definition

Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Mortgage-Backed Securities

-URI http://asc.fasb.org/extlink&oid=6517959

+ Details

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

- Details

Name:	us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsNonrecurringMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsRecurringMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Fair Value (Financial instruments Measured at Fair Value) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Securities available for sale:
Securities available for sale	$ 178,190us-gaap_AvailableForSaleSecurities	$ 164,034us-gaap_AvailableForSaleSecurities	$ 180,190us-gaap_AvailableForSaleSecurities
Recurring [Member] \| Fair Value [Member]
Securities available for sale:
Government-sponsored enterprise securities	44,365	27,521
Mortgage-backed securities	126,930	129,510
Corporate bonds	900	865
Equity securities	5,995	6,138
Securities available for sale	178,190	164,034
Recurring [Member] \| Quoted Prices in Market for Identical Assets (Level 1) [Member]
Securities available for sale:
Government-sponsored enterprise securities
Mortgage-backed securities
Corporate bonds
Equity securities
Securities available for sale
Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Securities available for sale:
Government-sponsored enterprise securities	44,365	27,521
Mortgage-backed securities	126,930	129,510
Corporate bonds	900	865
Equity securities	5,995	6,138
Securities available for sale	178,190	164,034
Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Securities available for sale:
Government-sponsored enterprise securities
Mortgage-backed securities
Corporate bonds
Equity securities
Securities available for sale
Nonrecurring [Member] \| Fair Value [Member]
Securities available for sale:
Impaired loans - covered	4,464	5,220
Impaired loans - non-covered	21,158	20,512
Other real estate - covered	2,055	2,350
Other real estate - non-covered	8,978	9,771
Nonrecurring [Member] \| Quoted Prices in Market for Identical Assets (Level 1) [Member]
Securities available for sale:
Impaired loans - covered
Impaired loans - non-covered
Other real estate - covered
Other real estate - non-covered
Nonrecurring [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Securities available for sale:
Impaired loans - covered
Impaired loans - non-covered
Other real estate - covered
Other real estate - non-covered
Nonrecurring [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Securities available for sale:
Impaired loans - covered	4,464	5,220
Impaired loans - non-covered	21,158	20,512
Other real estate - covered	2,055	2,350
Other real estate - non-covered	$ 8,978	$ 9,771