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Loans - TDR (Details)	3 Months Ended
	Mar. 31, 2018 USD ($) contract	Mar. 31, 2017 USD ($) contract	Dec. 31, 2017 USD ($)
Troubled debt restructurings - modified during the period
# of contracts | contract	6	4
Pre-modification recorded investment	$ 407,000	$ 244,000
Post-modification recorded investment	315,000	243,000
TDR's defaulted
Pre-modification outstanding recorded investment during the period	0	$ 0
Other information
Total Past Due	3,402,000		$ 5,606,000
Real estate - commercial | Owner occupied special purpose
Other information
Total Past Due	744,000		226,000
Real estate - commercial | Owner occupied general purpose
Other information
Total Past Due	63,000		1,136,000
Real estate - commercial | Non-owner occupied general purpose
Other information
Total Past Due	$ 441,000		593,000
Real estate - residential | Deferral
Troubled debt restructurings - modified during the period
# of contracts | contract	1
Pre-modification recorded investment	$ 165,000
Post-modification recorded investment	$ 74,000
Real estate - residential | Interest Rate Concession Below Normal Market [Member]
Troubled debt restructurings - modified during the period
# of contracts | contract	1
Pre-modification recorded investment	$ 24,000
Post-modification recorded investment	24,000
Real estate - residential | Investor
Other information
Total Past Due	92,000
Real estate - residential | Owner occupied
Other information
Total Past Due	327,000		74,000
Real estate - residential | Revolving and junior liens
Other information
Total Past Due	$ 722,000		769,000
Real estate - residential | Revolving and junior liens | Other
Troubled debt restructurings - modified during the period
# of contracts | contract	4	3
Pre-modification recorded investment	$ 218,000	$ 188,000
Post-modification recorded investment	217,000	$ 187,000
Real estate - residential | Revolving and junior liens | HAMP
Troubled debt restructurings - modified during the period
# of contracts | contract		1
Pre-modification recorded investment		$ 56,000
Post-modification recorded investment		$ 56,000
Commercial
Other information
Total Past Due	332,000		1,270,000
90 Days or Greater Past Due
Other information
Total Past Due	401,000		$ 248,000
90 Days or Greater Past Due | Real estate - residential | Revolving and junior liens
Other information
Total Past Due	$ 401,000

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