Allowance for Loan Losses (Details 1) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Rollforward of the allowance for loan losses
Beginning balance				$ 42,437				$ 42,289	$ 42,437	$ 42,289	$ 47,665
Charge-offs									(9,471)	(6,776)	(13,859)
Recoveries									2,241	2,174	2,316
Net charge-offs									(7,230)	(4,602)	(11,543)
Provision for loan losses									6,604	3,913	10,917
Benefit attributable to FDIC loss share agreements									(265)	(872)	(6,278)
Recoveries payable to FDIC									1,191	1,709	1,528
Provision for loan losses charged to operations	$ 1,650	$ 2,650	$ 1,430	1,800	$ 1,750	$ 750	$ 1,175	1,075	7,530	4,750	6,167
Ending balance	42,737				42,437				42,737	42,437	42,289
Period-End Amount Allocated to:
Individually evaluated for impairment												$ 4,141	$ 7,600	$ 10,256
Collectively evaluated for impairment												35,776	33,131	30,308
Acquired with deteriorated credit quality	42,737			42,437	42,437			42,289	42,437	42,289	47,665	42,737	42,437	42,289
Receivables Acquired with Deteriorated Credit Quality
Rollforward of the allowance for loan losses
Beginning balance				1,706				1,725	1,706	1,725
Ending balance	2,820				1,706				2,820	1,706	1,725
Period-End Amount Allocated to:
Acquired with deteriorated credit quality	2,820			1,706	1,706			1,725	1,706	1,725	1,725	2,820	1,706	1,725
Commercial, financial, agricultural
Rollforward of the allowance for loan losses
Beginning balance				4,186				3,305	4,186	3,305	3,090
Charge-offs									(2,725)	(943)	(1,516)
Recoveries									331	361	455
Net charge-offs									(2,394)	(582)	(1,061)
Provision for loan losses									3,716	1,489	1,297
Benefit attributable to FDIC loss share agreements									(61)	(64)	(204)
Recoveries payable to FDIC									39	38	183
Provision for loan losses charged to operations									3,694	1,463	1,276
Ending balance	5,486				4,186				5,486	4,186	3,305
Period-End Amount Allocated to:
Individually evaluated for impairment												446	6	5
Collectively evaluated for impairment												4,668	3,827	3,020
Acquired with deteriorated credit quality	5,486			4,186	4,186			3,305	4,186	3,305	3,090	5,486	4,186	3,305
Commercial, financial, agricultural | Receivables Acquired with Deteriorated Credit Quality
Rollforward of the allowance for loan losses
Beginning balance				353				280	353	280
Ending balance	372				353				372	353	280
Period-End Amount Allocated to:
Acquired with deteriorated credit quality	372			353	353			280	353	280	280	372	353	280
Real estate – construction
Rollforward of the allowance for loan losses
Beginning balance				1,852				1,415	1,852	1,415	1,091
Charge-offs									0	(26)	0
Recoveries									47	26	33
Net charge-offs									47	0	33
Provision for loan losses									364	435	290
Benefit attributable to FDIC loss share agreements									0	0	0
Recoveries payable to FDIC									117	2	1
Provision for loan losses charged to operations									481	437	291
Ending balance	2,380				1,852				2,380	1,852	1,415
Period-End Amount Allocated to:
Individually evaluated for impairment												1	20	0
Collectively evaluated for impairment												2,379	1,832	1,415
Acquired with deteriorated credit quality	2,380			1,852	1,852			1,415	1,852	1,415	1,091	2,380	1,852	1,415
Real estate – construction | Receivables Acquired with Deteriorated Credit Quality
Rollforward of the allowance for loan losses
Beginning balance				0				0	0	0
Ending balance	0				0				0	0	0
Period-End Amount Allocated to:
Acquired with deteriorated credit quality	0			0	0			0	0	0	0	0	0	0
Real estate – 1-4 family mortgage
Rollforward of the allowance for loan losses
Beginning balance				13,908				13,549	13,908	13,549	18,629
Charge-offs									(3,906)	(2,173)	(5,662)
Recoveries									997	1,064	1,325
Net charge-offs									(2,909)	(1,109)	(4,337)
Provision for loan losses									2,616	650	(452)
Benefit attributable to FDIC loss share agreements									(115)	(91)	(816)
Recoveries payable to FDIC									794	909	525
Provision for loan losses charged to operations									3,295	1,468	(743)
Ending balance	14,294				13,908				14,294	13,908	13,549
Period-End Amount Allocated to:
Individually evaluated for impairment												1,134	4,475	4,786
Collectively evaluated for impairment												12,319	9,177	8,483
Acquired with deteriorated credit quality	14,294			13,908	13,908			13,549	13,908	13,549	18,629	14,294	13,908	13,549
Real estate – 1-4 family mortgage | Receivables Acquired with Deteriorated Credit Quality
Rollforward of the allowance for loan losses
Beginning balance				256				280	256	280
Ending balance	841				256				841	256	280
Period-End Amount Allocated to:
Acquired with deteriorated credit quality	841			256	256			280	256	280	280	841	256	280
Real estate – commercial mortgage
Rollforward of the allowance for loan losses
Beginning balance				21,111				22,759	21,111	22,759	23,688
Charge-offs									(2,123)	(2,613)	(6,186)
Recoveries									757	614	436
Net charge-offs									(1,366)	(1,999)	(5,750)
Provision for loan losses									(879)	312	9,260
Benefit attributable to FDIC loss share agreements									(48)	(717)	(5,258)
Recoveries payable to FDIC									241	756	819
Provision for loan losses charged to operations									(686)	351	4,821
Ending balance	19,059				21,111				19,059	21,111	22,759
Period-End Amount Allocated to:
Individually evaluated for impairment												2,445	3,099	5,465
Collectively evaluated for impairment												15,008	16,916	16,130
Acquired with deteriorated credit quality	19,059			21,111	21,111			22,759	21,111	22,759	23,688	19,059	21,111	22,759
Real estate – commercial mortgage | Receivables Acquired with Deteriorated Credit Quality
Rollforward of the allowance for loan losses
Beginning balance				1,096				1,164	1,096	1,164
Ending balance	1,606				1,096				1,606	1,096	1,164
Period-End Amount Allocated to:
Acquired with deteriorated credit quality	1,606			1,096	1,096			1,164	1,096	1,164	1,164	1,606	1,096	1,164
Installment and Other
Rollforward of the allowance for loan losses
Beginning balance				1,380				1,261	1,380	1,261	1,167
Charge-offs									(717)	(1,021)	(495)
Recoveries									109	109	67
Net charge-offs									(608)	(912)	(428)
Provision for loan losses									787	1,027	522
Benefit attributable to FDIC loss share agreements									(41)	0	0
Recoveries payable to FDIC									0	4	0
Provision for loan losses charged to operations									746	1,031	522
Ending balance	1,518				1,380				1,518	1,380	1,261
Period-End Amount Allocated to:
Individually evaluated for impairment												115	0	0
Collectively evaluated for impairment												1,402	1,379	1,260
Acquired with deteriorated credit quality	1,518			1,380	1,380			1,261	1,380	1,261	1,167	1,518	1,380	1,261
Installment and Other | Receivables Acquired with Deteriorated Credit Quality
Rollforward of the allowance for loan losses
Beginning balance				1				1	1	1
Ending balance	1				1				1	1	1
Period-End Amount Allocated to:
Acquired with deteriorated credit quality	$ 1			$ 1	$ 1			$ 1	$ 1	$ 1	$ 1	$ 1	$ 1	$ 1