LOANS AND LEASES AND ALLOWANCE FOR LOAN AND LEASE LOSSES - Non Traditional Mortgage Performance Loan to Value Ratio (Detail) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2016 USD ($) Loan	Dec. 31, 2015 USD ($) Loan	Sep. 30, 2015 USD ($)
Financing Receivable, Recorded Investment [Line Items]
Loans	$ 6,568,791	$ 5,184,394	$ 4,730,077
Non-Traditional Mortgages (NTM)
Financing Receivable, Recorded Investment [Line Items]
Loans	$ 891,083	$ 785,908
Consumer | Non-Traditional Mortgages (NTM)
Financing Receivable, Recorded Investment [Line Items]
Count | Loan	697	689
Loans	$ 891,083	$ 785,908
Consumer | Non-Traditional Mortgages (NTM) | Green Loans
Financing Receivable, Recorded Investment [Line Items]
Loans	101,200	109,800
Consumer | Non-Traditional Mortgages (NTM) | Interest Only Loans
Financing Receivable, Recorded Investment [Line Items]
Loans	780,100	664,500
Consumer | Non-Traditional Mortgages (NTM) | Negative amortization
Financing Receivable, Recorded Investment [Line Items]
Loans	$ 9,900	$ 11,600
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens
Financing Receivable, Recorded Investment [Line Items]
Count | Loan	684	672
Loans	$ 887,374	$ 781,091
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Loan Portfolio Concentration Risk | Nontraditional First Lien Mortgage Loans Portfolio
Financing Receivable, Recorded Investment [Line Items]
Concentration risk percentage	100.00%	100.00%
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Green Loans
Financing Receivable, Recorded Investment [Line Items]
Count | Loan	112	121
Loans	$ 97,448	$ 105,131
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Green Loans | Loan Portfolio Concentration Risk | Green Loans Portfolio
Financing Receivable, Recorded Investment [Line Items]
Concentration risk percentage	100.00%	100.00%
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Interest Only Loans
Financing Receivable, Recorded Investment [Line Items]
Count | Loan	550	521
Loans	$ 780,069	$ 664,358
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Interest Only Loans | Loan Portfolio Concentration Risk | Interest Only Loans Portfolio
Financing Receivable, Recorded Investment [Line Items]
Concentration risk percentage	100.00%	100.00%
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Negative amortization
Financing Receivable, Recorded Investment [Line Items]
Count | Loan	22	30
Loans	$ 9,857	$ 11,602
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Negative amortization | Loan Portfolio Concentration Risk | Negative Amortization Loans Portfolio
Financing Receivable, Recorded Investment [Line Items]
Concentration risk percentage	100.00%	100.00%
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Less than 61
Financing Receivable, Recorded Investment [Line Items]
Count | Loan	251	228
Loans	$ 377,641	$ 264,612
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Less than 61 | Loan Portfolio Concentration Risk | Nontraditional First Lien Mortgage Loans Portfolio
Financing Receivable, Recorded Investment [Line Items]
Concentration risk percentage	42.60%	33.90%
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Less than 61 | Green Loans
Financing Receivable, Recorded Investment [Line Items]
Count | Loan	45	70
Loans	$ 39,237	$ 51,221
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Less than 61 | Green Loans | Loan Portfolio Concentration Risk | Green Loans Portfolio
Financing Receivable, Recorded Investment [Line Items]
Concentration risk percentage	40.30%	48.70%
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Less than 61 | Interest Only Loans
Financing Receivable, Recorded Investment [Line Items]
Count | Loan	193	141
Loans	$ 332,619	$ 208,120
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Less than 61 | Interest Only Loans | Loan Portfolio Concentration Risk | Interest Only Loans Portfolio
Financing Receivable, Recorded Investment [Line Items]
Concentration risk percentage	42.60%	31.30%
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Less than 61 | Negative amortization
Financing Receivable, Recorded Investment [Line Items]
Count | Loan	13	17
Loans	$ 5,785	$ 5,271
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Less than 61 | Negative amortization | Loan Portfolio Concentration Risk | Negative Amortization Loans Portfolio
Financing Receivable, Recorded Investment [Line Items]
Concentration risk percentage	58.70%	45.40%
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | 61-80
Financing Receivable, Recorded Investment [Line Items]
Count | Loan	359	336
Loans	$ 466,797	$ 456,843
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | 61-80 | Loan Portfolio Concentration Risk | Nontraditional First Lien Mortgage Loans Portfolio
Financing Receivable, Recorded Investment [Line Items]
Concentration risk percentage	52.50%	58.40%
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | 61-80 | Green Loans
Financing Receivable, Recorded Investment [Line Items]
Count | Loan	52	33
Loans	$ 47,442	$ 42,075
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | 61-80 | Green Loans | Loan Portfolio Concentration Risk | Green Loans Portfolio
Financing Receivable, Recorded Investment [Line Items]
Concentration risk percentage	48.60%	40.00%
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | 61-80 | Interest Only Loans
Financing Receivable, Recorded Investment [Line Items]
Count | Loan	298	291
Loans	$ 415,283	$ 408,662
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | 61-80 | Interest Only Loans | Loan Portfolio Concentration Risk | Interest Only Loans Portfolio
Financing Receivable, Recorded Investment [Line Items]
Concentration risk percentage	53.30%	61.60%
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | 61-80 | Negative amortization
Financing Receivable, Recorded Investment [Line Items]
Count | Loan	9	12
Loans	$ 4,072	$ 6,106
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | 61-80 | Negative amortization | Loan Portfolio Concentration Risk | Negative Amortization Loans Portfolio
Financing Receivable, Recorded Investment [Line Items]
Concentration risk percentage	41.30%	52.70%
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | 81-100
Financing Receivable, Recorded Investment [Line Items]
Count | Loan	44	50
Loans	$ 31,778	$ 37,228
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | 81-100 | Loan Portfolio Concentration Risk | Nontraditional First Lien Mortgage Loans Portfolio
Financing Receivable, Recorded Investment [Line Items]
Concentration risk percentage	3.60%	4.80%
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | 81-100 | Green Loans
Financing Receivable, Recorded Investment [Line Items]
Count | Loan	15	12
Loans	$ 10,769	$ 6,836
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | 81-100 | Green Loans | Loan Portfolio Concentration Risk | Green Loans Portfolio
Financing Receivable, Recorded Investment [Line Items]
Concentration risk percentage	11.10%	6.50%
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | 81-100 | Interest Only Loans
Financing Receivable, Recorded Investment [Line Items]
Count | Loan	29	37
Loans	$ 21,009	$ 30,167
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | 81-100 | Interest Only Loans | Loan Portfolio Concentration Risk | Interest Only Loans Portfolio
Financing Receivable, Recorded Investment [Line Items]
Concentration risk percentage	2.70%	4.50%
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | 81-100 | Negative amortization
Financing Receivable, Recorded Investment [Line Items]
Count | Loan	0	1
Loans	$ 0	$ 225
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | 81-100 | Negative amortization | Loan Portfolio Concentration Risk | Negative Amortization Loans Portfolio
Financing Receivable, Recorded Investment [Line Items]
Concentration risk percentage	0.00%	1.90%
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Greater than 100
Financing Receivable, Recorded Investment [Line Items]
Count | Loan	30	58
Loans	$ 11,158	$ 22,408
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Greater than 100 | Loan Portfolio Concentration Risk | Nontraditional First Lien Mortgage Loans Portfolio
Financing Receivable, Recorded Investment [Line Items]
Concentration risk percentage	1.30%	2.90%
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Greater than 100 | Green Loans
Financing Receivable, Recorded Investment [Line Items]
Count | Loan	0	6
Loans	$ 0	$ 4,999
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Greater than 100 | Green Loans | Loan Portfolio Concentration Risk | Green Loans Portfolio
Financing Receivable, Recorded Investment [Line Items]
Concentration risk percentage	0.00%	4.80%
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Greater than 100 | Interest Only Loans
Financing Receivable, Recorded Investment [Line Items]
Count | Loan	30	52
Loans	$ 11,158	$ 17,409
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Greater than 100 | Interest Only Loans | Loan Portfolio Concentration Risk | Interest Only Loans Portfolio
Financing Receivable, Recorded Investment [Line Items]
Concentration risk percentage	1.40%	2.60%
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Greater than 100 | Negative amortization
Financing Receivable, Recorded Investment [Line Items]
Count | Loan	0	0
Loans	$ 0	$ 0
Consumer | Non-Traditional Mortgages (NTM) | Green Loans (HELOC) - first liens | Greater than 100 | Negative amortization | Loan Portfolio Concentration Risk | Negative Amortization Loans Portfolio
Financing Receivable, Recorded Investment [Line Items]
Concentration risk percentage	0.00%	0.00%