SUPPLEMENTAL CASH FLOW INFORMATION - Supplemental Cash Flow Information (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash paid for:
Interest on borrowings	$ 102,402us-gaap_InterestPaid	$ 119,312us-gaap_InterestPaid	$ 164,364us-gaap_InterestPaid
Income tax	7,751us-gaap_IncomeTaxesPaidNet	4,447us-gaap_IncomeTaxesPaidNet	8,603us-gaap_IncomeTaxesPaidNet
Non-cash investing and financing activities:
Additions to other real estate owned	48,601	104,144	169,432
Additions to repossed properties	92,266us-gaap_TransferToOtherRealEstate	69,069us-gaap_TransferToOtherRealEstate	48,910us-gaap_TransferToOtherRealEstate
Loan securitizations	198,712fbp_NoncashLoanSecuritizations	355,506fbp_NoncashLoanSecuritizations	239,766fbp_NoncashLoanSecuritizations
Loans held for investment transferred to held for sale	0	181,620	2,641
Capitalization of servicing assets	4,321	7,649	6,348
Other Assets Held For Sale	0	2,225	0
Exchange of preferred stock-Series A through E	26,022	0	0
Preferred Stock [Member]
Non-cash investing and financing activities:
Exchange of preferred stock-Series A through E	26,943	0	0
Common Stock [Member] \| Series G Preferred Stock [Member]
Non-cash investing and financing activities:
New stock issued	$ 24,363	$ 0	$ 0

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This type of entry reflects the exchange of preferred stock for common stock of the entity.

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Noncash loan securitizations.

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Amount classified as other assets attributable to disposal group held for sale or disposed of.

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-Name Accounting Standards Codification

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-SubTopic 20

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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The amount of cash paid for interest during the period.

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Amount of real estate investments acquired through foreclosure for entities with a substantial portion of business acquiring and holding investment real estate.

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Amount of additions from purchases, assumption or transfer to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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The fair value of stock issued in noncash financing activities.

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Value of loans and leases held in the entity's portfolio transferred to loans and leases held-for-sale in noncash transactions.

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Value transferred from mortgage loans to real estate owned (REO) in noncash transactions.

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