LONG-TERM DEBT (FHLB Fixed Term Advances, Repayment Summary) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Collateral requirements [Abstract]
Percentage of book value of eligible mortgage loans pledged as collateral (in hundredths)	75.00%
Percentage of Bank's assets (in hundredths)	35.00%bxs_PercentageOfBanksAssets
FHLB fixed term advances, repayment summary, amount [Abstract]
2018	$ 48,148
2019	30,000
Total	$ 78,148
Minimum [Member]
FHLB fixed term advances, repayment summary, interest rate [Abstract]
Thereafter (in hundredths)	4.08%

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from two to three years of the Balance Sheet date.

+ References

No definition available.

+ Details

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- Definition

The percentage of the Bank's assets required to maintain as collateral, as part of the requirements to secure Federal Home Loan Bank borrowings.

+ References

No definition available.

+ Details

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- Definition

The percentage of book value (i.e., unpaid principal balance) of the Bank's eligible mortgage loans pledged as collateral, as part of the collateral requirements to secure Federal Home Loan Bank borrowings.

+ References

No definition available.

+ Details

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- Definition

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

+ References

+ Details

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- Definition

Amount of federal home loan bank advances maturing after the fifth fiscal year following the latest fiscal year.

+ 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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- Definition

Amount of federal home loan bank advances maturing in the fifth fiscal year following the latest fiscal year.

+ References

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