DEPOSITS - Interest Expenses on deposits (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Interest Expense, Deposits [Abstract]
Interest-bearing checking accounts	$ 5,208	$ 4,566	$ 4,914
Savings	14,298	12,520	12,392
Certificates of deposit	33,652	30,277	28,068
Brokered certificates of deposit	14,493	19,174	21,928
Interest expense on deposits	$ 67,651	$ 66,537	$ 67,302

Aggregate amount of interest expense on all deposits.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.6)
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

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Amount of interest expense on domestic brokered deposit liabilities.

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Amount of interest expense on domestic checking deposit liabilities.

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Interest expense incurred on all savings account deposits.

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The aggregate interest expense incurred on time deposits, including certificates of deposits, in domestic offices.

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