FAIR VALUE MEASUREMENTS - Additional Information (Detail) - USD ($)	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Fair Value Measurements Disclosure [Line Items]
Transfer of assets and liabilities between the hierarchy levels	$ 0	$ 0
Allocated allowance for loan losses	16,800,000
Provision for fair value measurements included in allowance for loan losses	14,000,000.0
Carrying amount of OREO	9,700,000
Written down of OREO	8,700,000
Loss from OREO included in earnings	1,000,000.0
Fair Value, Nonrecurring [Member]
Fair Value Measurements Disclosure [Line Items]
Impaired loans, carrying amount	30,900,000
Allocated allowance for loan losses			$ 5,000,000
Mortgage Servicing Rights [Member] | Fair Value, Nonrecurring [Member]
Fair Value Measurements Disclosure [Line Items]
Servicing asset, gross	43,300,000
Valuation allowance for impairment of recognized servicing assets, additions for expenses	9,600,000
Servicing asset	33,800,000
Mortgage Servicing Rights [Member] | Fair Value, Nonrecurring [Member] | Provision Expense [Member]
Fair Value Measurements Disclosure [Line Items]
Valuation allowance for impairment of recognized servicing assets, additions for expenses	$ 8,000,000.0