Acquired equity interest on disposal of loans held for sale.

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Payment to be made on pro rata basis.

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Percentage of weighted average yield with third party.

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The excess of the (1) par value of the trust preferred securities in the registrant's balance sheet over (2) the cash outflow to reacquire such securities.

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Trust Preferred Securities Winning Bid

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Variable rate trust preferred securities.

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Cash Flows between a transferor and a transferee attributable to collections reinvested in revolving period transfers related to either a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).

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Cash Flows between a transferor and a transferee attributable to purchases of previously transferred financial assets (or its underlying collateral) related to a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).

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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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Face (par) amount of debt instrument at time of issuance.

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Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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The increase (decrease) during the reporting period in the value of loans or securitized loans that are held with the intention to sell in the near future.

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The amount of interest incurred to a trust which has issued trust-preferred securities. In order to issue trust preferred securities, a sponsor forms a trust by investing a nominal amount of cash to purchase all of the voting common stock of the trust. The trust issues nonvoting, mandatorily redeemable preferred securities to outside investors in exchange for cash. The proceeds received from the issuance of the preferred securities, together with the cash received for issuing the common stock to the sponsor, is then loaned to the sponsor in exchange for a note which has the same terms as the trust preferred securities. Trust preferred securities possesses characteristics of both equity and debt issues and are generally issued by bank holding companies.

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Reflects the net positive or negative amount derived from subtracting from net proceeds of sale and the carrying amounts, net of allocated reserves, of financial assets transferred to third parties in transactions that qualify for sales treatment.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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The cash outflow to reacquire preferred stocks issued by a business trust or other special purpose entity, mainly established by a bank holding entity, to third party investors. The trust's assets are deeply subordinated debentures of the bank holding entity. Most trust preferred securities are subject to a mandatory redemption upon the repayment of the debentures.

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This is the principal amount outstanding for securitized loans only (across all types of loans).

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The cash inflow resulting from the sale of loans classified as held-for-sale, including proceeds from loans sold through mortgage securitization.

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Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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Description of qualitative information about the assumptions used to estimate fair value for servicing assets and servicing liabilities.

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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.

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No definition available.

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NON-CONSOLIDATED VARIABLE INTEREST ENTITIES AND SERVICING ASSETS - additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended				9 Months Ended		12 Months Ended
	Feb. 16, 2011	Apr. 30, 2004	Sep. 30, 2018	Mar. 31, 2018	Sep. 30, 2017	Jun. 30, 2016	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2014	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2016	Sep. 30, 2004
Servicing Liabilities At Fair Value [Line Items]
Principal amount of corporation serviced loans securitized through GNMA			$ 1,700,000				$ 1,700,000
Gains Losses On Extinguishment Of Debt			0		$ 1,391		2,316	$ 1,391
Carrying amount of servicing assets			27,593		25,999		27,593	25,999		$ 27,191	$ 25,255	$ 26,502	$ 26,244
Grantor Trust Fair Value			32,304				32,304			$ 27,191	25,255	$ 26,502	$ 26,244
Interest Expense Accrued Trust Preferred Securities						$ 31,200
Loans And Leases Receivable Gross Carrying Amount			$ 8,716,953		$ 8,877,214		8,716,953	$ 8,877,214			$ 8,850,476
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Qualitative Information			These sensitivities are hypothetical and should be used with caution. As the figures indicate, changes in fair value based on a 10% variation in assumptions generally cannot be extrapolated because the relationship between the change in assumption and the change in fair value may not be linear. Also, in this table, the effect of a variation in a particular assumption on the fair value of the servicing asset is calculated without changing any other assumption; in reality, changes in one factor may result in changes in another (for example, increases in market interest rates may result in lower prepayments), which may magnify or counteract the sensitivities
Prlp [Member]
Servicing Liabilities At Fair Value [Line Items]
Payment to be made on pro rata basis			35.00%
FirstBank [Member]
Servicing Liabilities At Fair Value [Line Items]
Payment to be made on pro rata basis			65.00%
Fbp Statutory Trust One [Member]
Servicing Liabilities At Fair Value [Line Items]
Trust Preferred Securities Repurchases				$ 23,800
Trust Preferred Securities Winning Bid				90.00%
Trust Preferred Securties Discount				10.00%
Fbp Statutory Trust One [Member] \| Trust Preferred Securities Subject to Mandatory Redemption [Member]
Servicing Liabilities At Fair Value [Line Items]
Gains Losses On Extinguishment Of Debt				$ 2,300
Fbp Statutory Trust One [Member] \| Junior Subordinated Deferrable Debentures [Member]
Servicing Liabilities At Fair Value [Line Items]
Trust Preferred Securities Repurchases				$ 23,800
Debt Instrument Face Amount		$ 103,100												$ 128,900
Cpg Gs [Member]
Servicing Liabilities At Fair Value [Line Items]
Loans sold to CPG	$ 269,300
Loans And Leases Receivable Gross Carrying Amount	136,100		$ 8,400				8,400
Cash realized on sale of loan	$ 88,500
Carrying amount of the Bank investment in CPG/GS									$ 0
Cpg Gs [Member] \| FirstBank [Member]
Servicing Liabilities At Fair Value [Line Items]
Acquired Equity interest on disposal of loans held for sale	35.00%
Minimum [Member] \| Prlp [Member]
Servicing Liabilities At Fair Value [Line Items]
Percentage Of Priority Interest To Be Received On Invested Capital			12.00%
Mortgage pass through trust certificates [Member]
Servicing Liabilities At Fair Value [Line Items]
Debt Instrument Description Of Variable Rate Basis			90-day LIBOR
Carrying amount of servicing assets			$ 20,000				20,000
Grantor Trust Fair Value			$ 14,600				$ 14,600
Percentage of weighted average yield with third party			4.57%
Variable Rate Demand Obligation [Member] \| Junior Subordinated Deferrable Debentures [Member]
Servicing Liabilities At Fair Value [Line Items]
Debt Instrument, Maturity Date, Description			The Junior Subordinated Deferrable Debentures issued by the Corporation in April 2004 and September 2004 mature on June 17, 2034 and September 20, 2034, respectively; however, under certain circumstances, the maturity of Junior Subordinated Deferrable Debentures may be shortened (such shortening would result in a mandatory redemption of the variable-rate trust-preferred securities).
Variable Rate Demand Obligation [Member] \| Fbp Statutory Trust One [Member]
Servicing Liabilities At Fair Value [Line Items]
Variable rate trust preferred securities		100,000
Proceeds of the issuance, together with proceeds of the purchase		3,100
Variable Rate Demand Obligation [Member] \| Fbp Statutory Trust One [Member] \| Junior Subordinated Deferrable Debentures [Member]
Servicing Liabilities At Fair Value [Line Items]
Principal amount of corporation's junior subordinated deferrable debentures		$ 103,100