Hurricane reserve release due to updated assesments of financial performance

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- Definition

Amount of increase (decrease) of allowance reserve for credit loss.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(3)
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-SubTopic 210
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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A valuation allowance for financing receivables that are expected to be uncollectible.

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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.

+ References

No definition available.

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ALLOWANCE FOR LOAN AND LEASE LOSSES - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Sep. 30, 2017
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance For Loan And Lease Losses Write Offs		$ 116,792	$ 134,770	$ 136,928
Construction Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance For Loan And Lease Losses Write Offs		8,296	3,607	1,770
Commercial Portfolio Segment [Member] \| General Allowance [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Financing Receivable Allowance For Credit Losses		5,700
Commercial Portfolio Segment [Member] \| Mortgage Receivable [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance For Loan And Lease Losses Write Offs		23,911	39,092	20,454
Commercial Portfolio Segment [Member] \| Commercial And Industrial Sector [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance For Loan And Lease Losses Write Offs		9,704	19,855	26,579
Commercial Portfolio Segment [Member] \| Commercial And Industrial Sector [Member] \| Puerto Rico [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance For Loan And Lease Losses Write Offs		1,300
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance For Loan And Lease Losses Period Increase Decrease	$ (1,600)
Commercial Portfolio Segment [Member] \| Floor Plan Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Financing Receivable Allowance For Credit Losses		400	700
Consumer Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance For Loan And Lease Losses Period Increase Decrease	$ 1,600
Allowance For Loan And Lease Losses Write Offs		50,106	44,030	54,504
Residential Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance For Loan And Lease Losses Write Offs		24,775	28,186	$ 33,621
Hurricane [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Financing Receivable Allowance For Credit Losses		19,200	55,600		$ 66,500
Net Loan Loss Reserve Release		16,900
Hurricane [Member] \| Puerto Rico [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Financing Receivable Allowance For Credit Losses		17,200	50,200
Hurricane [Member] \| Virgin Islands [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Financing Receivable Allowance For Credit Losses		2,000	5,400
Hurricane [Member] \| Construction Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Financing Receivable Allowance For Credit Losses		0	700
Hurricane [Member] \| Commercial Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Financing Receivable Allowance For Credit Losses		(5,700)
Hurricane [Member] \| Commercial Portfolio Segment [Member] \| Mortgage Receivable [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Financing Receivable Allowance For Credit Losses		3,800	7,500
Hurricane [Member] \| Commercial Portfolio Segment [Member] \| Commercial And Industrial Sector [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Financing Receivable Allowance For Credit Losses		3,400	13,100
Hurricane [Member] \| Consumer Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Financing Receivable Allowance For Credit Losses		3,200	25,000
Allowance For Loan And Lease Losses Write Offs		10,900
Hurricane [Member] \| Residential Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Financing Receivable Allowance For Credit Losses		$ 8,800	$ 9,200