Financing Receivable, Modified in Period, Average Capitalized Amount

No definition available.

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Namespace Prefix:	tcbi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amortized cost excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

+ Details

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

- Definition

Percentage, excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty to total financing receivables.

+ References

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481933/310-10-55-12A

Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-34

Reference 3: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 33
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-33

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of decrease in weighted-average contractual interest rate of financing receivable modified for debtor experiencing financial difficulty.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of increase in weighted-average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Loans and Allowance for Credit Losses on Loans - Summary of Amortized Cost of Gross Modified Loans Held for Investment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Financing Receivable, Modifications [Line Items]
Total modified in period	$ 64,015	$ 42,074	$ 107,759	$ 62,484
Percentage of Loans Held for Investment	0.26%	0.18%	0.43%	0.26%
Payment Deferral
Financing Receivable, Modifications [Line Items]
Total modified in period	$ 54,482	$ 9,492	$ 80,002	$ 27,327
Term Extension
Financing Receivable, Modifications [Line Items]
Total modified in period	9,533	11,002	10,898	12,819
Payment Deferral and Term Extension
Financing Receivable, Modifications [Line Items]
Total modified in period	0	21,580	16,859	22,338
Commercial
Financing Receivable, Modifications [Line Items]
Total modified in period	$ 64,015	$ 42,074	$ 90,900	$ 44,649
Percentage of Loans Held for Investment	0.26%	0.18%	0.36%	0.19%
Interest Rate Reduction	0.00%	0.00%	0.00%	0.00%
Term Extension (in months)	6 months
Payment Deferrals	$ 3,437	$ 5,762	$ 5,338	$ 5,897
Commercial \| Minimum
Financing Receivable, Modifications [Line Items]
Term Extension (in months)		10 months	4 months	6 months
Commercial \| Maximum
Financing Receivable, Modifications [Line Items]
Term Extension (in months)		26 months	6 months	26 months
Commercial \| Payment Deferral
Financing Receivable, Modifications [Line Items]
Total modified in period	54,482	$ 9,492	$ 80,002	$ 9,492
Commercial \| Term Extension
Financing Receivable, Modifications [Line Items]
Total modified in period	9,533	11,002	10,898	12,819
Commercial \| Payment Deferral and Term Extension
Financing Receivable, Modifications [Line Items]
Total modified in period	$ 0	$ 21,580	0	22,338
Commercial real estate
Financing Receivable, Modifications [Line Items]
Total modified in period			$ 16,859	$ 17,835
Percentage of Loans Held for Investment			0.07%	0.07%
Interest Rate Reduction			0.00%	0.00%
Term Extension (in months)			6 months
Payment Deferrals			$ 737	$ 369
Commercial real estate \| Payment Deferral
Financing Receivable, Modifications [Line Items]
Total modified in period			0	17,835
Commercial real estate \| Term Extension
Financing Receivable, Modifications [Line Items]
Total modified in period			0	0
Commercial real estate \| Payment Deferral and Term Extension
Financing Receivable, Modifications [Line Items]
Total modified in period			$ 16,859	$ 0