Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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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=84177426&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13537-108611

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. 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=82891408&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

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- Definition

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
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29.3)
-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 10
-Section S99
-Paragraph 6
-Subparagraph (SX 210.5-04.(c) Schedule IV)
-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

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LOANS AND LEASES AND ALLOWANCE FOR LOAN AND LEASE LOSSES - Non Traditional Mortgages Portfolio (Detail) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2017 USD ($) Loan	Dec. 31, 2016 USD ($) Loan	Sep. 30, 2016 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 6,226,897	$ 6,034,752	$ 6,568,791
Non-Traditional Mortgages (NTM)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 793,946	$ 885,148
Consumer \| Non-Traditional Mortgages (NTM)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Count \| Loan	579	663
Loans	$ 793,946	$ 885,148
Consumer \| Non-Traditional Mortgages (NTM) \| Loan Portfolio Concentration Risk \| Nontraditional Mortgage Loans Portfolio
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk percentage	100.00%	100.00%
Consumer \| Non-Traditional Mortgages (NTM) \| Loan Portfolio Concentration Risk \| Loan Portfolio
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk percentage	12.80%	14.70%
Consumer \| Non-Traditional Mortgages (NTM) \| Green Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 85,800	$ 91,000
Consumer \| Non-Traditional Mortgages (NTM) \| Interest Only Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	704,400	784,400
Consumer \| Non-Traditional Mortgages (NTM) \| Negative amortization
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 3,700	$ 9,800
Consumer \| Non-Traditional Mortgages (NTM) \| Green Loans (HELOC) - first liens
Accounts, Notes, Loans and Financing Receivable [Line Items]
Count \| Loan	567	651
Loans	$ 790,388	$ 881,589
Consumer \| Non-Traditional Mortgages (NTM) \| Green Loans (HELOC) - first liens \| Loan Portfolio Concentration Risk \| Nontraditional Mortgage Loans Portfolio
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk percentage	99.60%	99.60%
Consumer \| Non-Traditional Mortgages (NTM) \| Green Loans (HELOC) - first liens \| Green Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Count \| Loan	101	107
Loans	$ 82,289	$ 87,469
Consumer \| Non-Traditional Mortgages (NTM) \| Green Loans (HELOC) - first liens \| Green Loans \| Loan Portfolio Concentration Risk \| Nontraditional Mortgage Loans Portfolio
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk percentage	10.40%	9.90%
Consumer \| Non-Traditional Mortgages (NTM) \| Green Loans (HELOC) - first liens \| Interest Only Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Count \| Loan	455	522
Loans	$ 704,386	$ 784,364
Consumer \| Non-Traditional Mortgages (NTM) \| Green Loans (HELOC) - first liens \| Interest Only Loans \| Loan Portfolio Concentration Risk \| Nontraditional Mortgage Loans Portfolio
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk percentage	88.70%	88.60%
Consumer \| Non-Traditional Mortgages (NTM) \| Green Loans (HELOC) - first liens \| Negative amortization
Accounts, Notes, Loans and Financing Receivable [Line Items]
Count \| Loan	11	22
Loans	$ 3,713	$ 9,756
Consumer \| Non-Traditional Mortgages (NTM) \| Green Loans (HELOC) - first liens \| Negative amortization \| Loan Portfolio Concentration Risk \| Nontraditional Mortgage Loans Portfolio
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk percentage	0.50%	1.10%
Consumer \| Non-Traditional Mortgages (NTM) \| Green Loans (HELOC) - second liens
Accounts, Notes, Loans and Financing Receivable [Line Items]
Count \| Loan	12	12
Loans	$ 3,558	$ 3,559
Consumer \| Non-Traditional Mortgages (NTM) \| Green Loans (HELOC) - second liens \| Loan Portfolio Concentration Risk \| Nontraditional Mortgage Loans Portfolio
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk percentage	0.40%	0.40%
Consumer \| Non-Traditional Mortgages (NTM) \| Green Loans (HELOC) - second liens \| Green Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Count \| Loan	12	12
Loans	$ 3,558	$ 3,559
Consumer \| Non-Traditional Mortgages (NTM) \| Green Loans (HELOC) - second liens \| Green Loans \| Loan Portfolio Concentration Risk \| Nontraditional Mortgage Loans Portfolio
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk percentage	0.40%	0.40%