FAIR VALUE - Assets and Liabilities Measured at Fair Value on Recurring Basis Using Significant Unobservable Inputs (Level 3) (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Discount rate used for calculation of mortgage servicing rights value	14.50%	14.50%
Fair value input prepayment rate	30.00%	28.00%
Private Label Mbs [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value	$ 24,505
Discount rate used for calculation of mortgage servicing rights value	14.50%
US States And Political Subdivisions Member [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value	$ 1,969
Unobservable input prepayment rate	3.00%
Discounted Cash Flow [Member] | Private Label Mbs [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Valuation technique	Discounted cash flow
Discounted Cash Flow [Member] | US States And Political Subdivisions Member [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Valuation technique	Discounted cash flow
Minimum [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value input prepayment rate	21.45%	15.92%
Minimum [Member] | Private Label Mbs [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value input prepayment rate	21.45%
Fair value projected Cumulative Loss Rate	0.50%
Maximum [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value input prepayment rate	100.00%	100.00%
Maximum [Member] | Private Label Mbs [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value input prepayment rate	100.00%
Fair value projected Cumulative Loss Rate	80.00%