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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Namespace Prefix:	us-gaap_
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://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 2: 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 3: 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 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

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

+ 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 the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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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- 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		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Financing Receivable, Modifications [Line Items]
Total modified in period	$ 360	$ 6,643	$ 30,496	$ 58,617
Percentage of Loans Held for Investment	0.00%	0.03%	0.14%	0.28%
Payment Deferral
Financing Receivable, Modifications [Line Items]
Total modified in period	$ 360	$ 271	$ 6,762	$ 31,327
Term Extension
Financing Receivable, Modifications [Line Items]
Total modified in period	0	6,372	16,805	7,065
Payment Deferral and Term Extension
Financing Receivable, Modifications [Line Items]
Total modified in period	0	0	6,929	5,893
Interest Rate Reduction and Term Extension
Financing Receivable, Modifications [Line Items]
Total modified in period	0	0	0	14,332
Commercial
Financing Receivable, Modifications [Line Items]
Total modified in period	$ 360	$ 6,643	$ 14,665	$ 58,617
Percentage of Loans Held for Investment	0.00%	0.03%	0.07%	0.28%
Interest Rate Reduction	0.00%	0.00%	0.00%	0.70%
Payment Deferrals	$ 42	$ 59	$ 826	$ 5,139
Commercial \| Minimum
Financing Receivable, Modifications [Line Items]
Term Extension (in months)			12 months	1 month
Commercial \| Maximum
Financing Receivable, Modifications [Line Items]
Term Extension (in months)	0 years	1 month	13 months	36 months
Commercial \| Payment Deferral
Financing Receivable, Modifications [Line Items]
Total modified in period	$ 360	$ 271	$ 6,762	$ 31,327
Commercial \| Term Extension
Financing Receivable, Modifications [Line Items]
Total modified in period	0	6,372	974	7,065
Commercial \| Payment Deferral and Term Extension
Financing Receivable, Modifications [Line Items]
Total modified in period	0	0	6,929	5,893
Commercial \| Interest Rate Reduction and Term Extension
Financing Receivable, Modifications [Line Items]
Total modified in period	$ 0	$ 0	0	$ 14,332
Commercial real estate
Financing Receivable, Modifications [Line Items]
Total modified in period			$ 15,831
Percentage of Loans Held for Investment			0.07%
Interest Rate Reduction			0.00%
Term Extension (in months)			3 months
Payment Deferrals			$ 0
Commercial real estate \| Payment Deferral
Financing Receivable, Modifications [Line Items]
Total modified in period			0
Commercial real estate \| Term Extension
Financing Receivable, Modifications [Line Items]
Total modified in period			15,831
Commercial real estate \| Payment Deferral and Term Extension
Financing Receivable, Modifications [Line Items]
Total modified in period			0
Commercial real estate \| Interest Rate Reduction and Term Extension
Financing Receivable, Modifications [Line Items]
Total modified in period			$ 0