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Subordinated Debentures - Additional Information (Details) - USD ($)			9 Months Ended
	Feb. 19, 2016	Mar. 15, 2012	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Debt Instrument [Line Items]
Debt instrument, face amount			$ 50,000,000		$ 50,000,000
Subordinated Debentures
Debt Instrument [Line Items]
Percentage of principal amount redeemed		100.00%
Debt instrument redemption period			Mar. 15, 2012
Debt instrument maturity period			Mar. 15, 2037
Defer interest payments maximum period			5 years
Debt instrument interest rate description			three month London Interbank Offered Rate (LIBOR) plus 1.65%, which was 2.97% and 2.61% at September 30, 2017 and December 31, 2016
Debt instrument interest percentage			2.97%		2.61%
TFC Statutory Trust | Private Offering
Debt Instrument [Line Items]
Number of trust preferred securities	5,000
Trust preferred securities liquidation amount per preferred security	$ 1,000
TFC Statutory Trust | Subordinated Debentures
Debt Instrument [Line Items]
Debt instrument, face amount	$ 5,000,000
Debt valuation reserve	1,900,000
Debt amortization expense			$ 68,000	$ 55,000
TFC Statutory Trust | Fair Value, Inputs, Level 1
Debt Instrument [Line Items]
Subordinated debenture liability	$ 3,255,000
Other Assets
Debt Instrument [Line Items]
Investment in common stock			$ 155,000
London Interbank Offered Rate | Subordinated Debentures
Debt Instrument [Line Items]
Debt instrument, basis points			1.65%

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

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