GOODWILL - Goodwill by Segment (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($)
Goodwill [Line Items]
Goodwill as of January 1, 2019	$ 28,098
Mergers and acquisitions	6,303
Adjustments	4,231
Goodwill as of December 31, 2020	38,632
Mortgage Banking [Member]
Goodwill [Line Items]
Goodwill as of January 1, 2019	0
Mergers and acquisitions	574
Adjustments	385
Goodwill as of December 31, 2020	959
Consumer Retail Banking Segment [Member]
Goodwill [Line Items]
Goodwill as of January 1, 2019	0
Mergers and acquisitions	794
Adjustments	533
Goodwill as of December 31, 2020	1,327
Commercial And Corporate Segment [Member]
Goodwill [Line Items]
Goodwill as of January 1, 2019	0
Mergers and acquisitions	4,935
Adjustments	3,313
Goodwill as of December 31, 2020	8,248
United States Operations Segment [Member]
Goodwill [Line Items]
Goodwill as of January 1, 2019	28,098
Mergers and acquisitions	0
Adjustments	0
Goodwill as of December 31, 2020	$ 28,098

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10)(1))
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