LOANS AND LEASES AND ALLOWANCE FOR LOAN AND LEASE LOSSES - Non Traditional Mortgages Portfolio (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2015 USD ($) Loan	Dec. 31, 2014 USD ($) Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amount	$ 5,184,394	$ 3,949,122
Loan Portfolio \| Loan Portfolio Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk percentage	100.00%	100.00%
Non-Traditional Mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amount	$ 785,908	$ 350,575
Non-Traditional Mortgages \| Loan Portfolio \| Loan Portfolio Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk percentage	15.20%	8.90%
Consumer \| Non-Traditional Mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Count \| Loan	689	407
Amount	$ 785,908	$ 350,575
Consumer \| Non-Traditional Mortgages \| Nontraditional Mortgage Loans Portfolio \| Loan Portfolio Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk percentage	100.00%	100.00%
Consumer \| Non-Traditional Mortgages \| Loan Portfolio \| Loan Portfolio Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk percentage	15.20%	8.90%
Consumer \| Non-Traditional Mortgages \| First lien
Accounts, Notes, Loans and Financing Receivable [Line Items]
Count \| Loan	672	387
Amount	$ 781,091	$ 345,483
Consumer \| Non-Traditional Mortgages \| First lien \| Nontraditional Mortgage Loans Portfolio \| Loan Portfolio Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk percentage	99.30%	98.50%
Consumer \| Non-Traditional Mortgages \| Second lien
Accounts, Notes, Loans and Financing Receivable [Line Items]
Count \| Loan	17	20
Amount	$ 4,817	$ 5,092
Consumer \| Non-Traditional Mortgages \| Second lien \| Nontraditional Mortgage Loans Portfolio \| Loan Portfolio Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk percentage	0.70%	1.50%
Consumer \| Non-Traditional Mortgages \| Green Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amount	$ 109,800	$ 128,200
Consumer \| Non-Traditional Mortgages \| Green Loans \| First lien
Accounts, Notes, Loans and Financing Receivable [Line Items]
Count \| Loan	121	148
Amount	$ 105,131	$ 123,177
Consumer \| Non-Traditional Mortgages \| Green Loans \| First lien \| Nontraditional Mortgage Loans Portfolio \| Loan Portfolio Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk percentage	13.40%	35.10%
Consumer \| Non-Traditional Mortgages \| Green Loans \| Second lien
Accounts, Notes, Loans and Financing Receivable [Line Items]
Count \| Loan	16	19
Amount	$ 4,704	$ 4,979
Consumer \| Non-Traditional Mortgages \| Green Loans \| Second lien \| Nontraditional Mortgage Loans Portfolio \| Loan Portfolio Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk percentage	0.60%	1.40%
Consumer \| Non-Traditional Mortgages \| Interest Only Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amount	$ 664,500	$ 209,300
Consumer \| Non-Traditional Mortgages \| Interest Only Loans \| First lien
Accounts, Notes, Loans and Financing Receivable [Line Items]
Count \| Loan	521	207
Amount	$ 664,358	$ 209,207
Consumer \| Non-Traditional Mortgages \| Interest Only Loans \| First lien \| Nontraditional Mortgage Loans Portfolio \| Loan Portfolio Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk percentage	84.40%	59.70%
Consumer \| Non-Traditional Mortgages \| Interest Only Loans \| Second lien
Accounts, Notes, Loans and Financing Receivable [Line Items]
Count \| Loan	1	1
Amount	$ 113	$ 113
Consumer \| Non-Traditional Mortgages \| Interest Only Loans \| Second lien \| Nontraditional Mortgage Loans Portfolio \| Loan Portfolio Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk percentage	0.10%	0.10%
Consumer \| Non-Traditional Mortgages \| Negative amortization
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amount	$ 11,600	$ 13,100
Consumer \| Non-Traditional Mortgages \| Negative amortization \| First lien
Accounts, Notes, Loans and Financing Receivable [Line Items]
Count \| Loan	30	32
Amount	$ 11,602	$ 13,099
Consumer \| Non-Traditional Mortgages \| Negative amortization \| First lien \| Nontraditional Mortgage Loans Portfolio \| Loan Portfolio Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk percentage	1.50%	3.70%

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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Indicates the number of mortgages under each classification.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
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