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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

Level of performance goal measured by return on average tangible equity (ROATE) for a share based compensation plan.

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- Definition

The number of grants made on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested.

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- Definition

Level of performance goal measured by total shareholder return (TSR) for a share based compensation plan.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph g(1)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 14.F)
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14
-Section F

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph 64
-Subparagraph b
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph a
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(c)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

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Stock and Incentive Compensation Plans (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended				3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended			3 Months Ended		6 Months Ended			3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011 2005 Stock and Incentive Compensation Plan [Member] Stock option-based awards [Member]	Jun. 30, 2011 1997 Long Term Incentive Plan [Member] Stock option-based awards [Member]	Jun. 30, 2011 Stock option-based awards [Member]	Jun. 30, 2010 Stock option-based awards [Member]	Jun. 30, 2011 Stock option-based awards [Member]	Jun. 30, 2010 Stock option-based awards [Member]	Jun. 30, 2011 Restricted Stock [Member] Performance Based Award [Member]	Jun. 30, 2010 Restricted Stock [Member] Performance Based Award [Member]	Jun. 30, 2011 Restricted Stock [Member] Performance Based Award [Member]	Jun. 30, 2010 Restricted Stock [Member] Performance Based Award [Member]	Jan. 25, 2011 Restricted Stock [Member] Performance Based Award [Member]	Jun. 30, 2011 Restricted Stock [Member] Time Vested Award [Member]	Jun. 30, 2010 Restricted Stock [Member] Time Vested Award [Member]	Jun. 30, 2011 Restricted Stock [Member] Time Vested Award [Member]	Jun. 30, 2010 Restricted Stock [Member] Time Vested Award [Member]	Feb. 22, 2011 Restricted Stock [Member] Performance Based Excess Time-Vested [Member]	Jun. 30, 2011 Restricted Stock Units (RSUs) [Member] Performance Based Award [Member]	Jun. 30, 2010 Restricted Stock Units (RSUs) [Member] Performance Based Award [Member]	Jun. 30, 2011 Restricted Stock Units (RSUs) [Member] Performance Based Award [Member]	Jun. 30, 2010 Restricted Stock Units (RSUs) [Member] Performance Based Award [Member]	May 10, 2011 Restricted Stock Units (RSUs) [Member] Performance Based Award [Member]	Dec. 31, 2010 Restricted Stock Units (RSUs) [Member] Performance Based Award [Member]	Jan. 27, 2009 Restricted Stock Units (RSUs) [Member] Performance Based Award [Member]	Feb. 22, 2011 Restricted Stock Units (RSUs) [Member] Performance Based Excess Time-Vested [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights description					Stock options granted under the 2005 Plan vest 20% per year and have a contractual term of seven years	Stock option awards, which were granted under the 1997 Plan, had an exercise price equal to the market price of Trustmark's stock on the date of grant, vested equally over four years with a contractual ten-year term							The restriction period for performance awards covers a three-year vesting period. These awards are recognized on the straight-line method over the requisite service period. These awards provide for excess shares, if performance measures exceed 100%. Any excess shares granted are restricted for an additional three-year vesting period.
ROATE Performance measure (in hundredths)													100.00%
TSR Performance measure (in hundredths)													100.00%
Awarded shares (in shares)															53,863					75,162							23,123	23,123
Vested shares (in shares)																				8,959							23,123	23,123
Awarded shares in period (in shares)																		68,739
Fair value of stock (in dollars per share)																									$ 23.65	$ 20.82
Compensation expense - Stock and Incentive plans: [Abstract]
Compensation expense for stock and incentive plans	$ 1,051	$ 1,394	$ 2,226	$ 2,845			$ 32	$ 114	$ 100	$ 277	$ 218	$ 250	$ 441	$ 502		$ 754	$ 864	$ 1,501	$ 1,742		$ 47	$ 166	$ 184	$ 324