Percentage of total US government and sponsored agencies securities in relation to total investment securities.

No definition available.

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- Definition

Percentage of held to maturity securities issued by three of the largest municipalities in Puerto Rico.

+ References

No definition available.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Includes any additional disclosures related to the credit quality of financing receivables. This may include a description of a credit quality indicator or a description of how the internal risk ratings used by a company relate to the likelihood of loss.

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- Definition

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

+ References

No definition available.

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- Definition

This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which a previous OTTI was recognized and the investor does not intend to sell the debt security and it is not more likely than not that the investor will be required to sell the debt security before recovery of its amortized cost basis.

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- Definition

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.

+ References

No definition available.

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INVESTMENT SECURITIES - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Schedule Of Investments [Line Items]
Percentage Of Debt Securities Government And Government Sponsored Agencies	99.00%		99.00%
Amortized cost	$ 1,798,373,000		$ 1,798,373,000		$ 1,975,230,000
Fair value	1,803,688,000		1,803,688,000		$ 1,942,568,000
Available for sale Securities [Member] \| Private label MBS [Member]
Schedule Of Investments [Line Items]
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Additions, Additional Credit Losses	0	$ 0	$ 0	$ 0
Loans Receivable, Description of Variable Rate Basis			The interest rate on these private-label MBS is variable, tied to 3-month LIBOR and limited to the weighted-average coupon on the underlying collateral.
Available for sale Securities [Member] \| Private label MBS [Member] \| FICO Score, Greater than 700 [Member] \| LTV Less than 80 Percent [Member]
Schedule Of Investments [Line Items]
Financing Receivable, Credit Quality, Additional Information			The underlying mortgages are fixed-rate, single-family loans with original FICO scores (over 700) and moderate loan-to-value ratios (under 80%), as well as moderate delinquency levels.
Available for sale Securities [Member] \| PRHFA [Member] \| Zero-coupon bonds [Member]
Schedule Of Investments [Line Items]
Amortized cost	8,300,000		$ 8,300,000
Fair value	7,000,000.0		7,000,000.0
Available for sale Securities [Member] \| PRHFA [Member] \| Zero-coupon bonds [Member] \| Residential pass-through mortgage-backed securities [Member]
Schedule Of Investments [Line Items]
Amortized cost	4,300,000		4,300,000
Fair value	$ 2,900,000		$ 2,900,000
Held-to-maturity Securities [Member]
Schedule Of Investments [Line Items]
Percentage Of Held To Maturity Securities	70.00%		70.00%