FAIR VALUE - Impairment of Valuation Adjustments were Recorded for Assets Recognized at Fair Value (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Repayment rate used for the calculation of mortgage servicing rights value	32.00%us-gaap_FairValueInputsPrepaymentRate	28.89%us-gaap_FairValueInputsPrepaymentRate
Discount rate used for calculation of mortgage servicing rights value	14.50%us-gaap_FairValueInputsDiscountRate	14.50%us-gaap_FairValueInputsDiscountRate
Carrying Value of Loans Transferred to Loans Held For Sale			5.2
Mortgage Servicing Rights [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Repayment rate used for the calculation of mortgage servicing rights value	9.74%	8.90%	11.15%
Discount rate used for calculation of mortgage servicing rights value	10.60%	10.60%	12.08%

Carrying value of loans and leases held in the entity's portfolio transferred to loans and leases held-for-sale.

No definition available.

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- Details

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

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- Definition

Rate at which loans or a loan portfolio are expected to prepay principal balances, used as an input to measure fair value.

+ References

+ Details

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- Details

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