Acquired Loans - Components of the Allowance for Loan Losses on Acquired Loans (Details) - USD ($) $ in Thousands		3 Months Ended			9 Months Ended
		Sep. 30, 2016		Sep. 30, 2015	Sep. 30, 2016		Sep. 30, 2015
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period		$ 12,480		$ 12,629	$ 11,992		$ 12,059
Provision for loan losses, acquired loans		691		1,256	2,607		2,428
Loans charged-off		(2,590)		(2,566)	(5,041)		(5,584)
Recoveries		799		866	1,822		3,282
Net (charge-offs) recoveries		(1,791)		(1,700)	(3,219)		(2,302)
Balance at end of period		11,380		12,185	11,380		12,185
Noncovered Loans [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period		12,218		11,927	11,259		10,541
Transfers	[1]	215			215
Provision for loan losses, acquired loans		686		1,221	2,969		2,797
Loans charged-off		(2,590)		(2,456)	(4,959)		(5,024)
Recoveries		801		725	1,846		3,103
Net (charge-offs) recoveries		(1,789)		(1,731)	(3,113)		(1,921)
Balance at end of period		11,330		11,417	11,330		11,417
Covered Loans [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period		262		702	733		1,518
Transfers	[1]	(215)			(215)
Provision for loan losses, acquired loans		5		35	(362)		(369)
Loans charged-off				(110)	(82)		(560)
Recoveries		(2)		141	(24)		179
Net (charge-offs) recoveries		(2)		31	(106)		(381)
Balance at end of period		$ 50	[2]	$ 768	$ 50	[2]	$ 768

[1] The allowance for loan losses on covered acquired loans other than loans secured by 1-4 family residential properties transferred to the allowance for loan losses on noncovered acquired loans as a result of expiration of the related indemnification agreement with the FDIC on June 30, 2016.

[2] Trustmark’s loss share agreement with the FDIC covering the acquired covered loans other than loans secured by 1-4 family residential properties expired on June 30, 2016. Trustmark’s loss share agreement with the FDIC covering the acquired covered loans secured by 1-4 family residential properties will expire in 2021. Effective July 1, 2016, all acquired covered loans excluding the acquired covered loans secured by 1-4 family residential properties were reclassified to acquired noncovered loans.