Loans - Loan Modifications (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018 USD ($) contract
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts | contract	3
Pre-Modification Outstanding Recorded Investment	$ 208
Post-Modification Outstanding Recorded Investment	$ 226
Commercial, financial, and agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts | contract	0
Pre-Modification Outstanding Recorded Investment	$ 0
Post-Modification Outstanding Recorded Investment	$ 0
Real Estate Mortgages | Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts | contract	2
Pre-Modification Outstanding Recorded Investment	$ 102
Post-Modification Outstanding Recorded Investment	$ 120
Real Estate Mortgages | Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts | contract	1
Pre-Modification Outstanding Recorded Investment	$ 106
Post-Modification Outstanding Recorded Investment	$ 106