Allowance for Loan Losses - Allowance and Loans by Impairment Methodology (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Changes in the allowance for loan losses
Balance at the beginning of period		$ 37,066	$ 35,569	$ 35,606
Provision charged to operations		16,435	18,040	15,512
Loans charged off		(22,396)	(21,170)	(20,317)
Recoveries of loans previously charged off		4,621	4,627	4,768
Ending balance: individually evaluated for impairment		829	652
Ending balance, collectively evaluated for impairment		34,897	36,414
Balance at the end of period		35,726	37,066	35,569
Loans:
Ending balance		1,027,788	999,740
Ending balance: individually evaluated for impairment		10,896	5,825
Ending balance: collectively evaluated for impairment		1,013,789	984,659
Ending balance: acquired loans - purchase credit impaired		3,103	9,256
Real estate - residential mortgage
Changes in the allowance for loan losses
Balance at the beginning of period		2,559	2,471
Provision charged to operations		(127)	7
Loans charged off		(179)	(82)
Recoveries of loans previously charged off		118	163
Ending balance: individually evaluated for impairment		214	251
Ending balance, collectively evaluated for impairment		2,157	2,308
Balance at the end of period		2,371	2,559	2,471
Loans:
Ending balance		184,863	188,264
Ending balance: individually evaluated for impairment		3,636	3,408
Ending balance: collectively evaluated for impairment		180,735	183,637
Real estate - construction
Changes in the allowance for loan losses
Balance at the beginning of period		816	94
Provision charged to operations		(211)	722
Ending balance, collectively evaluated for impairment		605	816
Balance at the end of period		605	816	94
Loans:
Ending balance	[1]	44,782	55,732
Ending balance: collectively evaluated for impairment		44,782	55,732
Commercial, financial and agricultural
Changes in the allowance for loan losses
Balance at the beginning of period		7,393	7,755
Provision charged to operations		413	(481)
Loans charged off		(349)	(87)
Recoveries of loans previously charged off		21	206
Ending balance: individually evaluated for impairment		615	307
Ending balance, collectively evaluated for impairment		6,863	7,086
Balance at the end of period		7,478	7,393	7,755
Loans:
Ending balance	[2]	437,884	390,388
Ending balance: individually evaluated for impairment		6,907	1,865
Ending balance: collectively evaluated for impairment		428,505	380,764
Equity lines
Changes in the allowance for loan losses
Balance at the beginning of period		685	1,052
Provision charged to operations		43	(310)
Loans charged off		(42)	(57)
Recoveries of loans previously charged off		2
Ending balance, collectively evaluated for impairment		688	685
Balance at the end of period		688	685	1,052
Loans:
Ending balance		55,237	52,600
Ending balance: individually evaluated for impairment		31	32
Ending balance: collectively evaluated for impairment		55,067	52,290
Consumer Loan
Changes in the allowance for loan losses
Balance at the beginning of period		261	243
Provision charged to operations		82	63
Loans charged off		(301)	(281)
Recoveries of loans previously charged off		189	236
Ending balance: individually evaluated for impairment			94
Ending balance, collectively evaluated for impairment		231	167
Balance at the end of period		231	261	243
Loans:
Ending balance		13,018	8,399
Ending balance: individually evaluated for impairment		322	520
Ending balance: collectively evaluated for impairment		12,696	7,879
Consumer Finance
Changes in the allowance for loan losses
Balance at the beginning of period		25,352	23,954
Provision charged to operations		16,235	18,039
Loans charged off		(21,525)	(20,663)
Recoveries of loans previously charged off		4,291	4,022
Ending balance, collectively evaluated for impairment		24,353	25,352
Balance at the end of period		24,353	25,352	$ 23,954
Loans:
Ending balance		292,004	304,357
Ending balance: collectively evaluated for impairment		292,004	304,357
PCI | PCI Loans | CVBK
Loans:
Ending balance: acquired loans - purchase credit impaired		3,103	9,256
PCI | PCI Loans | CVBK | Real estate - residential mortgage
Loans:
Ending balance: acquired loans - purchase credit impaired		492	1,219
PCI | PCI Loans | CVBK | Commercial, financial and agricultural
Loans:
Ending balance: acquired loans - purchase credit impaired		2,472	7,759
PCI | PCI Loans | CVBK | Equity lines
Loans:
Ending balance: acquired loans - purchase credit impaired		$ 139	$ 278

[1] Includes the Corporation’s real estate construction lending and consumer real estate lot lending

[2] Includes the Corporation’s real estate construction lending and consumer real estate lot lending.Includes the Corporation’s commercial real estate lending, land acquisition and development lending, builder line lending and commercial business lending.