Acquired equity interest on disposal of loans held for sale.

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Weighted average yield of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Payment to be made on pro rata basis.

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Percentage of priority interest to be received on invested capital.

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Percentage of variation in assumptions.

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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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Description of reference rate used for variable rate of debt instrument.

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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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Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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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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Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer.

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

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The cash inflow from issuance of preferred stocks 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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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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NON-CONSOLIDATED VARIABLE INTEREST ENTITIES AND SERVICING ASSETS - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended
	Feb. 16, 2011	Apr. 30, 2004	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Servicing Liabilities At Fair Value [Line Items]
Servicing Asset at Amortized Cost			$ 30,753	$ 30,986	$ 32,710	$ 33,071
Servicing Asset At Fair Value Amount			$ 43,037	$ 42,132
Weighted-average yield			1.11%	1.03%
Loans and Leases Receivable, Gross			$ 11,100
Percentage Of Variation In Assumptions			10.00%
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 MSR 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.
Debt Securities, Available-for-sale, Allowance for Credit Loss			$ 711	$ 1,105	1,183	1,310
Junior subordinated debentures			$ 183,762	$ 183,762
Minimum [Member]
Servicing Liabilities At Fair Value [Line Items]
Percentage Of Variation In Assumptions			10.00%
Maximum [Member]
Servicing Liabilities At Fair Value [Line Items]
Percentage Of Variation In Assumptions			20.00%
FirstBank [Member]
Servicing Liabilities At Fair Value [Line Items]
Payment To Be Made On Pro Rata Basis			65.00%
Prlp [Member] \| Minimum [Member]
Servicing Liabilities At Fair Value [Line Items]
Percentage Of Priority Interest To Be Received On Invested Capital			12.00%
CPG/GS [Member] \| Commercial Portfolio Segment [Member]
Servicing Liabilities At Fair Value [Line Items]
Loans held for sale sold	$ 269,300
Loans and Leases Receivable, Gross	136,100
CPG/GS [Member] \| Commercial Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member]
Servicing Liabilities At Fair Value [Line Items]
Cash realized on sale of loan	$ 88,500
Acquired equity interest	35.00%
CPG/GS [Member] \| Prlp [Member]
Servicing Liabilities At Fair Value [Line Items]
Payment To Be Made On Pro Rata Basis			35.00%
Variable Rate Demand Obligation [Member] \| Junior Subordinated Debt [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 TRuPs). As of each March 31, 2022 and December 31, 2021, these TRuPs amounted to $183.8 million.
Variable Rate Demand Obligation [Member] \| Statutory Trust One [Member]
Servicing Liabilities At Fair Value [Line Items]
Proceeds from Issuance of Trust Preferred Securities		$ 100,000
Proceeds of the issuance, together with proceeds of the purchase		3,100
Principal amount of corporation's junior subordinated deferrable debentures		103,100
Variable Rate Demand Obligation [Member] \| Statutory Trust Two [Member]
Servicing Liabilities At Fair Value [Line Items]
Proceeds from Issuance of Trust Preferred Securities		125,000
Proceeds of the issuance, together with proceeds of the purchase		3,900
Principal amount of corporation's junior subordinated deferrable debentures		$ 128,900
MBS [Member]
Servicing Liabilities At Fair Value [Line Items]
Weighted-average yield			1.34%	1.26%
Debt Securities, Available-for-sale, Allowance for Credit Loss			$ 403	$ 797
MBS [Member] \| Private label [Member]
Servicing Liabilities At Fair Value [Line Items]
Servicing Asset at Amortized Cost			9,500
Servicing Asset At Fair Value Amount			$ 6,900
Weighted-average yield			2.96%
Debt Securities, Available-for-sale, Allowance for Credit Loss			$ 403	$ 797	$ 875	$ 1,002
MBS [Member] \| Private label [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Servicing Liabilities At Fair Value [Line Items]
Debt Instrument Description Of Variable Rate Basis			3-month LIBOR
GNMA [Member]
Servicing Liabilities At Fair Value [Line Items]
Principal amount of corporation serviced loans securitized through GNMA			$ 2,100,000