LOAN PORTFOLIO - Credit Risk Payment Activity (Detail) - USD ($) $ in Thousands	Sep. 30, 2016		Dec. 31, 2015		Sep. 30, 2015
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	$ 8,863,654		$ 9,112,382		$ 9,140,462
Other Residential Mortgage Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	3,168,006	[1]	3,201,578
Auto loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	858,797		934,980
Finance Leases [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	229,577		229,165
Other Consumer Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	1,497,812		1,597,984
Residential Real Estate [Member] | Fhava Guaranteed Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	131,936	[2]	143,141	[3]
Residential Real Estate [Member] | Other Residential Mortgage Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	3,168,006		3,201,578
Residential Real Estate [Member] | Performing Financing Receivable [Member] | Fhava Guaranteed Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	131,936	[2]	143,141	[3]
Residential Real Estate [Member] | Performing Financing Receivable [Member] | Other Residential Mortgage Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	2,840,791		2,861,811
Residential Real Estate [Member] | Purchased Credit Impaired [Member] | Fhava Guaranteed Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	0	[2],[4]	0	[3],[5]
Residential Real Estate [Member] | Purchased Credit Impaired [Member] | Other Residential Mortgage Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	165,014	[4]	170,766	[5]
Residential Real Estate [Member] | Nonperforming Financing Receivable [Member] | Fhava Guaranteed Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	0	[2]	0	[3]
Residential Real Estate [Member] | Nonperforming Financing Receivable [Member] | Other Residential Mortgage Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	162,201		169,001
Consumer [Member] | Auto loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	858,797		934,980
Consumer [Member] | Finance Leases [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	229,577		229,165
Consumer [Member] | Other Consumer Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	639,015		663,004
Consumer [Member] | Performing Financing Receivable [Member] | Auto loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	844,182		917,545
Consumer [Member] | Performing Financing Receivable [Member] | Finance Leases [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	227,608		226,706
Consumer [Member] | Performing Financing Receivable [Member] | Other Consumer Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	630,320		652,146
Consumer [Member] | Purchased Credit Impaired [Member] | Auto loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	0	[4]	0	[5]
Consumer [Member] | Purchased Credit Impaired [Member] | Finance Leases [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	0	[4]	0	[5]
Consumer [Member] | Purchased Credit Impaired [Member] | Other Consumer Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	0	[4]	0	[5]
Consumer [Member] | Nonperforming Financing Receivable [Member] | Auto loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	14,615		17,435
Consumer [Member] | Nonperforming Financing Receivable [Member] | Finance Leases [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	1,969		2,459
Consumer [Member] | Nonperforming Financing Receivable [Member] | Other Consumer Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans And Leases Receivable Gross Carrying Amount	$ 8,695		$ 10,858

[1] According to the Corporation's delinquency policy and consistent with the instructions for the preparation of the Consolidated Financial Statements for Bank Holding Companies (FR Y-9C) required by the Federal Reserve Board, residential mortgage, commercial mortgage, and construction loans are considered past due when the borrower is in arrears two or more monthly payments. FHA/VA government-guaranteed loans, other residential mortgage loans, commercial mortgage loans, land loans and construction-residential loans past due 30-59 days as of September 30, 2016 amounted to $8.7 million, $144.3 million, $7.6 million, $0.7 million and $0.3 million, respectively.

[2] It is the Corporation's policy to report delinquent residential mortgage loans insured by the FHA or guaranteed by the VA as past due loans 90 days and still accruing as opposed to non-performing loans since the principal repayment is insured. These balances include $29.6 million of residential mortgage loans insured by the FHA or guaranteed by the VA, which are over 15 months delinquent and are no longer accruing interest as of September 30, 2016.

[3] It is the Corporation's policy to report delinquent residential mortgage loans insured by the FHA or guaranteed by the VA as past due loans 90 days and still accruing as opposed to non-performing loans since the principal repayment is insured. These balances include $37.3 million of residential mortgage loans insured by the FHA or guaranteed by the VA, which are over 15 months delinquent and are no longer accruing interest as of December 31, 2015.

[4] PCI loans are excluded from non-performing statistics due to the application of the accretion method, under which these loans will accrete interest income over the remaining life of the loans using estimated cash flow analysis.

[5] PCI loans are excluded from non-performing statistics due to the application of the accretion method, under which these loans will accrete interest income over the remaining life of the loans using estimated cash flow analysis.