DERIVATIVE INSTRUMENTS (Offsetting Of Derivative Assets And Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Offsetting Assets And Liabilities [Line Items]
Gross Amount Recognized	$ 24,181	$ 30,573
Gross Amount Offset
Net Amount Recognized	24,181	30,573
Net Amount	24,181bxs_DerivativeFairValueAssetsNet	30,573bxs_DerivativeFairValueAssetsNet
Gross Amount Recognized	411,373	450,380
Gross Amount Offset
Net Amount Recognized	411,373	450,380
Financial Instruments	(388,166)	(421,028)
Financial Collateral Pledged	(22,004)	(29,249)
Net Amount	1,203bxs_DerivativeFairValueLiabilitiesNet	103bxs_DerivativeFairValueLiabilitiesNet
Forward Commitments [Member]
Offsetting Assets And Liabilities [Line Items]
Gross Amount Recognized	2,177	1,324
Gross Amount Offset
Net Amount Recognized	2,177	1,324
Net Amount	2,177	1,324
Gross Amount Recognized	1,203	103
Gross Amount Offset
Net Amount Recognized	1,203	103
Net Amount	1,203	103
Loan/Lease Interest Rate Swaps [Member]
Offsetting Assets And Liabilities [Line Items]
Gross Amount Recognized	22,004	29,249
Gross Amount Offset
Net Amount Recognized	22,004	29,249
Net Amount	22,004	29,249
Gross Amount Recognized	22,004	29,249
Gross Amount Offset
Net Amount Recognized	22,004	29,249
Financial Collateral Pledged	(22,004)	(29,249)
Repurchase Arrangements [Member]
Offsetting Assets And Liabilities [Line Items]
Gross Amount Recognized	388,166	421,028
Gross Amount Offset
Net Amount Recognized	388,166	421,028
Financial Instruments	$ (388,166)	$ (421,028)

Fair value of the assets of a derivative or group of derivatives.

No definition available.

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- Definition

Fair value of the liabilities of a derivative or group of derivatives.

+ References

No definition available.

+ Details

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- Definition

Fair value of derivative asset, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

+ References

No definition available.

+ Details

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- Definition

+ References

No definition available.

+ Details

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- Definition

Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226003-175313

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=20225523&loc=SL20225862-175312

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (a),(c)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959

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- Definition

Fair value before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226000-175313

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=20225523&loc=SL20225862-175312

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (a),(c)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959

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- Definition

Fair value of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be offset against an obligation to return collateral under a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=20225523&loc=SL20225862-175312

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41678-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 11

-URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226011-175313

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 9

-URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226006-175313

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- Definition

Fair value before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

+ References

+ Details

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- Definition

Fair value of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be offset against a right to receive collateral under a master netting arrangement.

+ References

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- Definition

Fair value of asset associated with financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

+ References

+ Details

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