DEPOSITS - Components of Interest Expense on Deposits (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Deposits [Abstract]
Interest expense on deposits	$ 9,876	$ 16,245	$ 33,718	$ 52,587
Accretion of premium from acquisitions	(243)	(284)	(1,089)	(285)
Amortization of broker placement fees	49	127	177	437
Interest expense on deposits	$ 9,682	$ 16,088	$ 32,806	$ 52,739

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=120399700&loc=SL114874048-224260

Name:	us-gaap_InterestExpenseDeposits
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration