ACQUISITIONS - Schedule of Hypothetical Shares Issued In Merger (Details) - CBTX	Sep. 30, 2022 shares
Pro Forma
Business Acquisition [Line Items]
Number of shares issued in acquisition (in shares)	36,768,000
Percentage Ownership	100.00%
CBTX
Business Acquisition [Line Items]
Number of shares issued in acquisition (in shares)	52,152,000
Percentage Ownership	100.00%
CBTX \| CBTX shareholders
Business Acquisition [Line Items]
Number of shares issued in acquisition (in shares)	24,015,000
Percentage Ownership	46.00%
CBTX \| Allegiance shareholders
Business Acquisition [Line Items]
Number of shares issued in acquisition (in shares)	28,137,000
Percentage Ownership	54.00%
CBTX \| Pro Forma \| CBTX shareholders
Business Acquisition [Line Items]
Number of shares issued in acquisition (in shares)	16,931,000
Percentage Ownership	46.00%
CBTX \| Pro Forma \| Allegiance shareholders
Business Acquisition [Line Items]
Number of shares issued in acquisition (in shares)	19,837,000
Percentage Ownership	54.00%

Number of shares of equity interests issued or issuable to acquire entity.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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