Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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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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LOAN PORTFOLIO - Corporation's TDR Activity (Parenthetical) (Detail) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable Modifications [Line Items]
Loans held for investment transferred to held for sale			$ 90,319	$ 0	$ 10,332
Charge-off			116,792	134,770	136,928
Nonperforming Financial Instruments [Member]
Financing Receivable Modifications [Line Items]
Charge Offs Loans Held For Sale			22,200
Loans held for investment transferred to held for sale			74,400
Financing Receivable Significant Sales		$ 16,300
Nonperforming Financial Instruments [Member] \| Puerto Rico Electric Power Authority [Member]
Financing Receivable Modifications [Line Items]
Financing Receivable Significant Sales	$ 64,000
Entity Loan Modification Program [Member] \| Puerto Rico Electric Power Authority [Member]
Financing Receivable Modifications [Line Items]
Charge-off				$ 10,700
Entity Loan Modification Program [Member] \| Nonperforming Financial Instruments [Member]
Financing Receivable Modifications [Line Items]
Charge-off					1,300
Financing Receivable Significant Sales					$ 16,300
Entity Loan Modification Program [Member] \| Nonperforming Financial Instruments [Member] \| Loans Tranferred To Held For Sale [Member]
Financing Receivable Modifications [Line Items]
Charge Offs Loans Held For Sale			8,500
Loans held for investment transferred to held for sale			$ 34,500