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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).

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Gross number of excess share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

The period between the balance sheet date and expiration for stock and incentive compensation awards under the plan, which may be expressed in a decimal value for number of years.

+ References

No definition available.

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- Definition

Annual vesting percentage of stock options.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Value of one unit of performance-based restricted stock award in terms of number of shares of Trustmark's common stock.

+ References

No definition available.

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- Definition

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

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-Name Staff Accounting Bulletin (SAB)

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- Definition

Description of the period of time over which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, which may be expressed in a variety of ways (for example, in years, month and year).

+ 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.

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- Definition

The decrease in the number of shares that could be issued attributable to the lapse of rights to exercise previously issued stock options under the terms of the option agreements under the plan during the reporting period.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph A240

-Subparagraph b(1)(g)

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Subparagraph b(1)(f)

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

+ References

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

-Publisher FASB

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-Topic 718

-SubTopic 10

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-Subparagraph (c)(1)(i)-(ii)

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- Definition

Number of share options (or share units) exercised during the current period.

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-Topic 505

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Stock and Incentive Compensation Plans (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Dec. 31, 2011
Compensation expense - Stock and Incentive plans: [Abstract]
Compensation expense for stock and incentive plans	$ 1,127	$ 1,174
Stock option-based awards [Member]
Stock and incentive plan [Roll Forward]
Outstanding/Nonvested shares or units, beginning of period	1,205,100
Granted	0
Granted - excess shares	0
Exercised or released from restriction	(1,375)
Expired	(16,575)
Forfeited	0
Outstanding/Nonvested shares or units, end of period	1,187,150
Compensation expense - Stock and Incentive plans: [Abstract]
Compensation expense for stock and incentive plans	0	67
Stock option-based awards [Member] \| 2005 Stock and Incentive Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vesting percentage per year (in hundredths)	20.00%
Stock and incentive compensation plan, contractual term (in years)	7 Y
Stock option-based awards [Member] \| 1997 Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock and incentive compensation plan, contractual term (in years)	10 Y
Vesting period	4 Y
Performance Based Award [Member]
Stock and incentive plan [Roll Forward]
Outstanding/Nonvested shares or units, beginning of period	179,421
Granted	55,295
Granted - excess shares	0
Exercised or released from restriction	(71,500)
Expired	0
Forfeited	(1,463)
Outstanding/Nonvested shares or units, end of period	161,753
Performance Based Award [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
ROATE Performance measure (in hundredths)	100.00%
TSR Performance measure (in hundredths)	100.00%
Vesting period	3 Y
Compensation expense - Stock and Incentive plans: [Abstract]
Compensation expense for stock and incentive plans	219	223
Performance Based Award [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of stock (in dollars per share)			$ 23.65
Vesting period			2 Y
Value of one unit of performance-based restricted stock award in terms of number of shares of Trustmark's common stock (in shares)			1
Compensation expense - Stock and Incentive plans: [Abstract]
Compensation expense for stock and incentive plans	0	137
Performance Based Excess Time-Vested [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 Y
Time Vested Award [Member]
Stock and incentive plan [Roll Forward]
Outstanding/Nonvested shares or units, beginning of period	334,356
Granted	77,006
Granted - excess shares	63,610
Exercised or released from restriction	(89,815)
Expired	0
Forfeited	(2,842)
Outstanding/Nonvested shares or units, end of period	382,315
Time Vested Award [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	36 M
Compensation expense - Stock and Incentive plans: [Abstract]
Compensation expense for stock and incentive plans	$ 908	$ 747