Loans (Details 3) - USD ($) $ in Thousands	Feb. 28, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Recorded Investment [Line Items]
Total loans		$ 337,100	$ 306,771	$ 286,146
Construction and Land Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		33,862	31,150		$ 31,150
Residential [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		6,770	5,202
Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		27,092	25,948
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		133,099	116,218		116,218
Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		66,021	69,256
Non-Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		57,944	38,037
Multifamily [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		8,824	8,537
Farmland [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		310	388
Consumer Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		81,250	83,594		83,594
Home equity lines [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		20,691	20,333
First Deed of Trust [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		54,791	56,776
Second Deed of Trust [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		5,768	6,485
Commercial and industrial loans (except those secured by real estate) [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		39,390	20,086
Guaranteed student loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		47,398	53,989
Consumer And Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		2,101	1,734
Risk Rated 1-4 [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		319,778	288,129
Risk Rated 1-4 [Member] | Construction and Land Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		32,112	29,255
Risk Rated 1-4 [Member] | Residential [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		6,770	5,202
Risk Rated 1-4 [Member] | Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		25,342	24,053
Risk Rated 1-4 [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		125,676	108,873
Risk Rated 1-4 [Member] | Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		58,788	64,261
Risk Rated 1-4 [Member] | Non-Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		57,944	35,887
Risk Rated 1-4 [Member] | Multifamily [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		8,634	8,337
Risk Rated 1-4 [Member] | Farmland [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		310	388
Risk Rated 1-4 [Member] | Consumer Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		74,548	75,490
Risk Rated 1-4 [Member] | Home equity lines [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		19,501	18,539
Risk Rated 1-4 [Member] | First Deed of Trust [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		49,648	51,200
Risk Rated 1-4 [Member] | Second Deed of Trust [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		5,399	5,751
Risk Rated 1-4 [Member] | Commercial and industrial loans (except those secured by real estate) [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		39,390	18,873
Risk Rated 1-4 [Member] | Guaranteed student loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		46,009	53,989
Risk Rated 1-4 [Member] | Consumer And Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		2,043	1,649
Risk Rated 5 [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		9,653	9,385
Risk Rated 5 [Member] | Construction and Land Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		1,648	572
Risk Rated 5 [Member] | Residential [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		0	0
Risk Rated 5 [Member] | Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		1,648	572
Risk Rated 5 [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		3,755	5,105
Risk Rated 5 [Member] | Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		3,565	2,850
Risk Rated 5 [Member] | Non-Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		0	2,055
Risk Rated 5 [Member] | Multifamily [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		190	200
Risk Rated 5 [Member] | Farmland [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		0	0
Risk Rated 5 [Member] | Consumer Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		3,459	3,273
Risk Rated 5 [Member] | Home equity lines [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		487	435
Risk Rated 5 [Member] | First Deed of Trust [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		2,847	2,710
Risk Rated 5 [Member] | Second Deed of Trust [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		125	128
Risk Rated 5 [Member] | Commercial and industrial loans (except those secured by real estate) [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		0	373
Risk Rated 5 [Member] | Guaranteed student loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		739	0
Risk Rated 5 [Member] | Consumer And Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		52	62
Risk Rate 6 [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		7,669	9,257
Risk Rate 6 [Member] | Construction and Land Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		102	1,323
Risk Rate 6 [Member] | Residential [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		0	0
Risk Rate 6 [Member] | Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		102	1,323
Risk Rate 6 [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		3,668	2,240
Risk Rate 6 [Member] | Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		3,668	2,145
Risk Rate 6 [Member] | Non-Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		0	95
Risk Rate 6 [Member] | Multifamily [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		0	0
Risk Rate 6 [Member] | Farmland [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		0	0
Risk Rate 6 [Member] | Consumer Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		3,243	4,831
Risk Rate 6 [Member] | Home equity lines [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		703	1,359
Risk Rate 6 [Member] | First Deed of Trust [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		2,296	2,866
Risk Rate 6 [Member] | Second Deed of Trust [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		244	606
Risk Rate 6 [Member] | Commercial and industrial loans (except those secured by real estate) [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		0	840
Risk Rate 6 [Member] | Guaranteed student loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		650	0
Risk Rate 6 [Member] | Consumer And Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		6	23
Risk Rated 7 [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		0	0
Risk Rated 7 [Member] | Construction and Land Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		0	0
Risk Rated 7 [Member] | Residential [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		0	0
Risk Rated 7 [Member] | Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans			0
Risk Rated 7 [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		0	0
Risk Rated 7 [Member] | Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		0	0
Risk Rated 7 [Member] | Non-Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		0	0
Risk Rated 7 [Member] | Multifamily [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		0	0
Risk Rated 7 [Member] | Farmland [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		0	0
Risk Rated 7 [Member] | Consumer Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		0			$ 0
Risk Rated 7 [Member] | Home equity lines [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	$ 0	0
Risk Rated 7 [Member] | First Deed of Trust [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		0	0
Risk Rated 7 [Member] | Second Deed of Trust [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		0	0
Risk Rated 7 [Member] | Commercial and industrial loans (except those secured by real estate) [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans			0
Risk Rated 7 [Member] | Guaranteed student loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		0	0
Risk Rated 7 [Member] | Consumer And Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans		$ 0	$ 0