Debt Covenant, Percent of Return on Assets, Below Required Minimum

No definition available.

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- Definition

The increase (decrease) during the reporting period in other miscellaneous borrowings not otherwise defined in the taxonomy.

+ References

No definition available.

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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.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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- 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.

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- Definition

Amount of advances from the Federal Home Loan Bank (FHLB).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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- Definition

Discloses the single interest rate [if] applicable to the advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

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BORROWINGS AND BORROWING CAPACITY - Narrative (Details) - USD ($)	1 Months Ended	3 Months Ended	9 Months Ended		12 Months Ended
	Oct. 31, 2015	Sep. 30, 2017	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Increase (decrease) in other borrowings					$ 18,000,000	$ 10,100,000
Repayments of debt	$ 27,500,000		$ 103,000,000	$ 20,000,000
Borrowing Agreement \| Prime Rate
Debt Instrument [Line Items]
Basis spread on variable rate			0.25%
Interest rate, effective percentage		4.00%	4.00%
Allegiance Bank
Debt Instrument [Line Items]
Return on assets, below required minimum		0.47%
Federal Home Loan Bank of Dallas
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 886,600,000.0	$ 886,600,000.0
Remaining borrowing capacity		646,000,000	646,000,000
Long-term line of credit		240,600,000	240,600,000
Outstanding amount		33,600,000	33,600,000
Federal Home Loan Bank of Dallas \| Expire in October 2017
Debt Instrument [Line Items]
Outstanding amount		25,000,000	25,000,000
Federal Home Loan Bank of Dallas \| Expire in February 2018
Debt Instrument [Line Items]
Outstanding amount		3,100,000	3,100,000
Federal Home Loan Bank of Dallas \| Expire in August 2018
Debt Instrument [Line Items]
Outstanding amount		5,500,000	5,500,000
Federal Home Loan Bank of Dallas \| Short-term Debt
Debt Instrument [Line Items]
Federal Home Loan Bank, advances		$ 207,000,000	$ 207,000,000
Federal Home Loan Bank of Dallas \| Short-term Debt \| Weighted Average
Debt Instrument [Line Items]
Federal Home Loan Bank, advances, interest rate		1.32%	1.32%