Limit For Loss Risk Transferred

No definition available.

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- Definition

Reference Pool Of Mortgage Warehouse Loans

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of short-term and long-term debt and lease obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13,16)
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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-Topic 944
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-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399

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-Section 55
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-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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Period Type:	instant

- 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

No definition available.

+ Details

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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- Details

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- Details

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- Details

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Long-Term Debt (Details) - USD ($)		3 Months Ended
Long-Term Debt (Details) - USD ($)	Mar. 09, 2021	Mar. 31, 2021	Mar. 31, 2020	Jan. 31, 2014	Sep. 21, 2012
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Trust preferred securities issued				$ 175,000,000.0	$ 111,000,000.0
Stated interest rate				5.25%	6.50%
Reference pool of mortgage warehouse loans		$ 2,200,000,000
Limit for loss risk transferred		$ 275,000,000.0
Senior Unsecured Credit-Linked Notes
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Face amount	$ 275,000,000
Weighted-average interest rate during the year		5.54%
LIBOR \| Minimum \| Senior Unsecured Credit-Linked Notes
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest rate on subordinated debentures, spread on variable rate	4.50%
LIBOR \| Maximum \| Senior Unsecured Credit-Linked Notes
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest rate on subordinated debentures, spread on variable rate	4.25%
Texas Capital Bancshares Statutory Trust I
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Trust preferred securities issued		$ 10,310,000
Texas Capital Statutory Trust II
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Trust preferred securities issued		10,310,000
Texas Capital Statutory Trust III
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Trust preferred securities issued		25,774,000
Texas Capital Statutory Trust IV
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Trust preferred securities issued		25,774,000
Texas Capital Statutory Trust V
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Trust preferred securities issued		41,238,000
Trust preferred subordinated debentures
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Total borrowings		$ 113,400,000
Weighted-average interest rate during the year		2.19%	3.80%
Trust preferred subordinated debentures \| Texas Capital Bancshares Statutory Trust I \| LIBOR
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest rate on subordinated debentures, spread on variable rate		3.35%
Trust preferred subordinated debentures \| Texas Capital Statutory Trust II \| LIBOR
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest rate on subordinated debentures, spread on variable rate		3.25%
Trust preferred subordinated debentures \| Texas Capital Statutory Trust III \| LIBOR
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest rate on subordinated debentures, spread on variable rate		1.51%
Trust preferred subordinated debentures \| Texas Capital Statutory Trust IV \| LIBOR
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest rate on subordinated debentures, spread on variable rate		1.71%
Trust preferred subordinated debentures \| Texas Capital Statutory Trust V \| LIBOR
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest rate on subordinated debentures, spread on variable rate		1.60%