NATURAL DISASTERS- Additional information (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2015
catastrophe line items
Financing Receivable Allowance For Credit Losses		$ 230,870	$ 214,070	$ 230,870	$ 214,070	$ 173,485	$ 205,603	$ 234,454	$ 240,710
Loans And Leases Receivable Impaired Nonperforming Nonaccrual Of Interest	[1],[2],[3]	473,132		473,132			560,094
Marketing And Advertising Expense		3,244	$ 3,169	9,717	$ 11,220
Hurricane [Member]
catastrophe line items
Financing Receivable Allowance For Credit Losses		66,500		66,500
Loss Contingency Receivable		2,900		2,900
Loss And Expenses Catastrophic Events		3,500
Disaster Response Plan Costs		2,900
Marketing And Advertising Expense		600
Residential Mortgage [Member]
catastrophe line items
Loans And Leases Receivable Impaired Nonperforming Nonaccrual Of Interest		178,530		178,530			$ 160,867
Residential Mortgage [Member] | Hurricane [Member]
catastrophe line items
Loans And Leases Receivable Impaired Nonperforming Nonaccrual Of Interest Additions		23,200
Consumer Loan [Member]
catastrophe line items
Loans And Leases Receivable Impaired Nonperforming Nonaccrual Of Interest		26,500		$ 26,500
Consumer Loan [Member] | Hurricane [Member]
catastrophe line items
Loans And Leases Receivable Impaired Nonperforming Nonaccrual Of Interest Additions		$ 5,400

[1] Amount excludes purchased-credit impaired ("PCI") loans with a carrying value of approximately $157.8 million and $165.8 million as of September 30, 2017 and December 31, 2016, respectively, primarily mortgage loans acquired from Doral Bank in the first quarter of 2015 and from Doral Financial in the second quarter of 2014, as further discussed below. These loans are not considered non-performing due to the application of the accretion method, under which these loans will accrete interest income over the remaining life of the loans using an estimated cash flow analysis.

[2] Excludes $8.3 million and $8.1 million of non-performing loans held for sale as of September 30, 2017 and December 31, 2016, respectively.

[3] Non-performing loans exclude $388.8 million and $384.9 million of Troubled Debt Restructuring ("TDR") loans that are in compliance with modified terms and in accrual status as of September 30, 2017 and December 31, 2016, respectively.