The fair value of investments that represented 5% or more of the total plan asset value as of period end.

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The threshold of total plan asset value for which the fair value of individual investments are disclosed.

+ References

No definition available.

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The percentage of the fair value of debt securities to the fair value of total plan assets held as of the measurement date.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 5

-Subparagraph d(1)

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The percentage of the fair value of equity securities to the fair value of total plan assets held as of the measurement date.

+ References

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The amount of the aggregate benefits expected to be paid in the five fiscal years thereafter (the aggregate amount of benefits expected to be paid in years 6 through 10 after the date of the latest statement of financial position).

+ References

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The amount of the benefits expected to be paid in Year 5.

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The amount of the benefits expected to be paid in Year 4.

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The amount of the benefits expected to be paid in Year 1.

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The amount of the benefits expected to be paid in Year 3.

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- Definition

The amount of the benefits expected to be paid in Year 2.

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- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

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The percentage of the fair value of investments other than debt securities, equity securities, and real estate to the fair value of total plan assets held as of the measurement date.

+ References

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Target allocation maximum percentage of investments in debt securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

No definition available.

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Target allocation minimum percentage of investments in debt securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

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Target allocation maximum percentage of investments in equity securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

No definition available.

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Target allocation minimum percentage of investments in equity securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

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No definition available.

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Target allocation percentage in other than debt securities, equity securities, and real estate to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

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No definition available.

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The aggregate percentage of the fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of total plan assets held as of the measurement date.

+ References

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PENSION, OTHER POST RETIREMENT BENEFIT AND PROFIT SHARING PLANS, Information about Plan Assets (Details) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Pension Benefits [Member]
Actual weighted-average asset allocation [Abstract]
Equity securities (in hundredths)	36.87%	57.26%
Debt securities (in hundredths)	58.16%	37.18%
Cash and equivalents (in hundredths)	4.97%	5.56%
Total (in hundredths)	100.00%	100.00%
Target asset allocations [Abstract]
Equity securities, minimum (in hundredths)	40.00%
Equity securities, maximum (in hundredths)	60.00%
Debt securities, minimum (in hundredths)	40.00%
Debt securities, maximum (in hundredths)	60.00%
Cash and equivalents (in hundredths)	0.00%
Expected future benefit payments:
2012		$ 12,629,000
2013		9,705,000
2014		10,450,000
2015		11,950,000
2016		10,790,000
2017-2021		58,568,000
Fair value of plan assets [Abstract]
Fair value of plan assets	195,004,000	197,536,000	180,217,000	116,136,000
Threshold of plan asset value at which individual investments are disclosed (in hundredths)	5.00%
Pension Benefits [Member] \| Fidelity Advisor New Insight [Member]
Fair value of plan assets [Abstract]
Fair value of investments that represent 5% or more of total plan asset value	10,382,000
Pension Benefits [Member] \| Franklin Mutual Discovery Z Fund [Member]
Fair value of plan assets [Abstract]
Fair value of investments that represent 5% or more of total plan asset value	10,489,000
Pension Benefits [Member] \| T. Rowe Price Equity Income Fund [Member]
Fair value of plan assets [Abstract]
Fair value of investments that represent 5% or more of total plan asset value	10,724,000
Pension Benefits [Member] \| Vanguard Total Bond Market Index Institutional Fund [Member]
Fair value of plan assets [Abstract]
Fair value of investments that represent 5% or more of total plan asset value	21,641,000
Pension Benefits [Member] \| Brokered Certificates of Deposit [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	4,965,000	7,881,000
Pension Benefits [Member] \| Brokered Certificates of Deposit [Member] \| Level 1 [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	0	0
Pension Benefits [Member] \| Brokered Certificates of Deposit [Member] \| Level 2 [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	4,965,000	7,881,000
Pension Benefits [Member] \| Brokered Certificates of Deposit [Member] \| Level 3 [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	0	0
Pension Benefits [Member] \| U.S. Agency Debt Obligations [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	70,757,000	33,433,000
Pension Benefits [Member] \| U.S. Agency Debt Obligations [Member] \| Level 1 [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	0	0
Pension Benefits [Member] \| U.S. Agency Debt Obligations [Member] \| Level 2 [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	70,757,000	33,433,000
Pension Benefits [Member] \| U.S. Agency Debt Obligations [Member] \| Level 3 [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	0	0
Pension Benefits [Member] \| Mutual Funds [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	112,995,000	150,964,000
Pension Benefits [Member] \| Mutual Funds [Member] \| Level 1 [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	112,995,000	150,964,000
Pension Benefits [Member] \| Mutual Funds [Member] \| Level 2 [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	0	0
Pension Benefits [Member] \| Mutual Funds [Member] \| Level 3 [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	0	0
Pension Benefits [Member] \| Common stock of BancorpSouth, Inc. [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	907,000	1,312,000
Pension Benefits [Member] \| Common stock of BancorpSouth, Inc. [Member] \| Level 1 [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	907,000	1,312,000
Pension Benefits [Member] \| Common stock of BancorpSouth, Inc. [Member] \| Level 2 [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	0	0
Pension Benefits [Member] \| Common stock of BancorpSouth, Inc. [Member] \| Level 3 [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	0	0
Pension Benefits [Member] \| Money Market Funds [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	4,701,000	3,568,000
Pension Benefits [Member] \| Money Market Funds [Member] \| Level 1 [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	0	0
Pension Benefits [Member] \| Money Market Funds [Member] \| Level 2 [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	4,701,000	3,568,000
Pension Benefits [Member] \| Money Market Funds [Member] \| Level 3 [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	0	0
Pension Benefits [Member] \| Total Investments [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	194,325,000	197,158,000
Pension Benefits [Member] \| Total Investments [Member] \| Level 1 [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	113,902,000	152,276,000
Pension Benefits [Member] \| Total Investments [Member] \| Level 2 [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	80,423,000	44,882,000
Pension Benefits [Member] \| Total Investments [Member] \| Level 3 [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	0	0
Pension Benefits [Member] \| Accrued Interest and Dividends [Member]
Fair value of plan assets [Abstract]
Fair value of plan assets	679,000	378,000
Basic Plan [Member] \| Common stock of BancorpSouth, Inc. [Member]
Actual weighted-average asset allocation [Abstract]
Equity securities (in hundredths)	0.46%	0.66%
Fair value of plan assets [Abstract]
Fair value of plan assets	$ 907,000	$ 1,200,000