LOAN PORTFOLIO - Selected Information on TDRs Includes Recorded Investment by Loan Class and Modification Type (Detail) - USD ($) $ in Thousands	Jun. 30, 2017		Mar. 31, 2017	Dec. 31, 2016		Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	$ 568,543		$ 602,364	$ 647,048		$ 670,991	$ 659,104	$ 661,591
Interest Rate Below Market [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	35,826			37,645
Maturity of Term Extension [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	25,682			88,535
Combination of reduction in interest rate and extension of maturity [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	347,093			355,812
Forgiveness of principal and/or interest [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	36,605			38,055
Other [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	123,337	[1]		127,001	[2]
Non Fha Va Residential Mortgage Loans [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	368,505			375,809
Non Fha Va Residential Mortgage Loans [Member] | Interest Rate Below Market [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	26,636			29,254
Non Fha Va Residential Mortgage Loans [Member] | Maturity of Term Extension [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	8,347			8,373
Non Fha Va Residential Mortgage Loans [Member] | Combination of reduction in interest rate and extension of maturity [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	273,798			280,588
Non Fha Va Residential Mortgage Loans [Member] | Forgiveness of principal and/or interest [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	0			0
Non Fha Va Residential Mortgage Loans [Member] | Other [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	59,724	[1]		57,594	[2]
Commercial Mortgage Loans [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	50,065			48,742
Commercial Mortgage Loans [Member] | Interest Rate Below Market [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	6,625			6,044
Commercial Mortgage Loans [Member] | Maturity of Term Extension [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	2,157			2,007
Commercial Mortgage Loans [Member] | Combination of reduction in interest rate and extension of maturity [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	30,796			30,005
Commercial Mortgage Loans [Member] | Forgiveness of principal and/or interest [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	0			0
Commercial Mortgage Loans [Member] | Other [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	10,487	[1]		10,686	[2]
Commercial And Industrial Loan [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	65,886			133,521
Commercial And Industrial Loan [Member] | Interest Rate Below Market [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	2,146			2,111
Commercial And Industrial Loan [Member] | Maturity of Term Extension [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	4,444			66,830
Commercial And Industrial Loan [Member] | Combination of reduction in interest rate and extension of maturity [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	15,372			16,359
Commercial And Industrial Loan [Member] | Forgiveness of principal and/or interest [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	861			863
Commercial And Industrial Loan [Member] | Other [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	43,063	[1]		47,358	[2]
Construction Loans [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	45,000
Consumer Auto Loans [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	23,994			24,875
Consumer Auto Loans [Member] | Interest Rate Below Market [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	0			0
Consumer Auto Loans [Member] | Maturity of Term Extension [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	1,488			1,706
Consumer Auto Loans [Member] | Combination of reduction in interest rate and extension of maturity [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	14,949			14,698
Consumer Auto Loans [Member] | Forgiveness of principal and/or interest [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	0			0
Consumer Auto Loans [Member] | Other [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	7,557	[1]		8,471	[2]
Finance Leases [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	2,492			2,647
Finance Leases [Member] | Interest Rate Below Market [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	0			0
Finance Leases [Member] | Maturity of Term Extension [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	284			366
Finance Leases [Member] | Combination of reduction in interest rate and extension of maturity [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	2,208			2,281
Finance Leases [Member] | Forgiveness of principal and/or interest [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	0			0
Finance Leases [Member] | Other [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	0	[1]		0	[2]
Other Consumer Loans [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	12,548			14,842
Other Consumer Loans [Member] | Interest Rate Below Market [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	419			236
Other Consumer Loans [Member] | Maturity of Term Extension [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	2,295			2,518
Other Consumer Loans [Member] | Combination of reduction in interest rate and extension of maturity [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	7,780			9,662
Other Consumer Loans [Member] | Forgiveness of principal and/or interest [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	224			299
Other Consumer Loans [Member] | Other [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	1,830	[1]		2,127	[2]
Commercial Construction [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	35,520			36,893
Commercial Construction [Member] | Interest Rate Below Market [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	0			0
Commercial Construction [Member] | Maturity of Term Extension [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	0			0
Commercial Construction [Member] | Combination of reduction in interest rate and extension of maturity [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	0			0
Commercial Construction [Member] | Forgiveness of principal and/or interest [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	35,520			36,893
Commercial Construction [Member] | Other [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	0	[1]		0	[2]
Residential Construction [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	352			357
Residential Construction [Member] | Interest Rate Below Market [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	0			0
Residential Construction [Member] | Maturity of Term Extension [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	0			0
Residential Construction [Member] | Combination of reduction in interest rate and extension of maturity [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	0			0
Residential Construction [Member] | Forgiveness of principal and/or interest [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	0			0
Residential Construction [Member] | Other [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	352	[1]		357	[2]
Land Construction [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	9,181			9,362
Land Construction [Member] | Interest Rate Below Market [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	0			0
Land Construction [Member] | Maturity of Term Extension [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	6,667			6,735
Land Construction [Member] | Combination of reduction in interest rate and extension of maturity [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	2,190			2,219
Land Construction [Member] | Forgiveness of principal and/or interest [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	0			0
Land Construction [Member] | Other [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Modifications, Recorded Investment	$ 324	[1]		$ 408	[2]

[1] Other concessions granted by the Corporation include deferral of principal and/or interest payments for a period longer than what would be considered insignificant, payment plans under judicial stipulation, or a combination of the concessions listed in the table.

[2] Other concessions granted by the Corporation include deferral of principal and/or interest payments for a period longer than what would be considered insignificant, payment plans under judicial stipulation or a combination of the concessions listed in the table.