Loans - Loans purchased through its acquisition of IBTX (Details) - USD ($) $ in Thousands		3 Months Ended
Jan. 01, 2025	Mar. 31, 2025
Business Acquisition [Line Items]
Allowance for credit losses at acquisition		$ (118,643)
Independent
Business Acquisition [Line Items]
Book value of acquired loans at acquisition	$ 3,081,440
Allowance for credit losses at acquisition	(118,643)
Non-credit discount at acquisition	(151,993)
Carrying value or book value of acquired loans at acquisition	$ 2,810,804

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 20
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Amount, excluding accrued interest, of allowance for credit loss at acquisition date of financing receivable purchased with credit deterioration. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Amount at par value of financing receivable purchased with credit deterioration.

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Amount at purchase price of financing receivable purchased with credit deterioration.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of discount (premium) attributable to other factors on financing receivable purchased with credit deterioration.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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