CREDIT QUALITY ASSESSMENT (Summary of Impaired Loans) (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Credit Quality Assessment [Abstract]
Impaired loans with a specific allowance	$ 17,848	$ 12,876
Impaired loans without a specific allowance	8,292	9,334
Total impaired loans	26,140	22,210
Allowance for loan and lease losses related to impaired loans	5,341	4,924
Allowance for loan and lease losses related to loans collectively evaluated	47,748	48,562
Total allowance for loan and lease losses	53,089	53,486
Average impaired loans for the period	24,175	20,211
Contractual interest income due on impaired loans during the period	646	2,513
Interest income on impaired loans recognized on a cash basis	110	506
Interest income on impaired loans recognized on an accrual basis	$ 42	$ 138

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Loans and Leases Receivable, Impaired, Contractual Interest Income

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No definition available.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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