MORTGAGE BANKING ACTIVITIES - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]
Originations of loans held for sale from mortgage banking	$ 1,024,307	$ 1,007,720
Proceeds from sale of mortgage loans held-for-sale	976,100	927,700
Net gain on sale of mortgage loans held for sale	$ 29,700	$ 34,400
Margin on sale of mortgage loans held for sale	2.90%	3.41%
Loan origination fees	$ 4,000	$ 3,500
Loans sold	8,400	9,800
Decrease in fair value of derivative instruments	9,600
Gain on sale	6,200
Provision for loss reimbursement on sold loans	(359)	845
Representations and Warranties Obligations and Corporate Guarantees
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]
Provision for loss reimbursement on sold loans	379	1,300
Initial provision for loan repurchases	$ 738	$ 483

Loss Contingency, Accrual, Provision, Initial Loan Repurchases

No definition available.

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- Definition

Provision charged for the period based on estimated losses for sold loans that may have to be subsequently repurchased and amounts that may have to be paid to reimburse certain investor losses due to defects that occurred in the origination of the loans.

+ References

No definition available.

+ Details

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- Definition

Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale, Margin

+ References

No definition available.

+ Details

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- Definition

Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale, Origination Fee

+ References

No definition available.

+ Details

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- Definition

Transfers Of Financial Assets Accounted For As Sale, Initial Fair Value Of Assets Obtained As Proceeds, Sold

+ References

No definition available.

+ Details

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- Definition

Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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- Definition

Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5618551-113959

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- Definition

The amount of cash paid for the origination of mortgages that are held for sale.

+ References

+ Details

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- Definition

The cash inflow from sales of loans that are secured with real estate mortgages and are held with the intention to resell in the near future.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3461-108585

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- Definition

Reflects, by transferred financial asset type, the amount of sales proceeds in excess of or deficient from the sum of the carrying amounts of transferred financial assets plus transaction costs, including those transactions in which the seller/transferor has continuing involvement with the financial assets that have been transferred.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64830801&loc=d3e107207-111719

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 10
-Section 40
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=65892426&loc=d3e96813-111708

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- Definition

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.

+ References

No definition available.

+ Details

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