Defined benefit plan net periodic benefit cost increase (decrease).

No definition available.

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- Definition

For a defined benefit plan, the previous minimum required employer contribution for the period, prior to government enactment.

+ References

No definition available.

+ Details

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- Definition

Number of years service required before retirement benefits vest.

+ References

No definition available.

+ Details

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Expected Long-Term Rate of Return on Plan Assets
-URI http://asc.fasb.org/extlink&oid=6512046

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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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.

+ References

No definition available.

+ Details

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Defined Benefit and Other Postretirement Benefits - Additional Information (Details) - Trustmark Capital Accumulation Plan [Member] - USD ($)	3 Months Ended	6 Months Ended		9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2016	Jun. 30, 2016	Sep. 30, 2016	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Years of service required to vest				3 years
Expected rate of return on plan assets			6.00%
Increase in periodic benefit costs	$ 664,000
Scenario Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets		2.50%
Trustmark's minimum required contribution to Trustmark Capital Accumulation Plan					$ 0