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Loans - TDR (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2018 USD ($) contract	Sep. 30, 2017 USD ($) contract	Sep. 30, 2018 USD ($) contract	Sep. 30, 2017 USD ($) contract	Dec. 31, 2017 USD ($)
Troubled debt restructurings - modified during the period
# of contracts | contract	6		17
Pre-modification recorded investment	$ 791,000	$ 155,000	$ 1,600,000	$ 399,000
Post-modification recorded investment	782,000	$ 147,000	1,473,000	$ 388,000
TDR's defaulted
# of contracts | contract		2		6
Pre-modification outstanding recorded investment during the period			0	$ 0
Other information
Total Past Due	$ 16,881,000		$ 16,881,000		$ 5,606,000
Other
Troubled debt restructurings - modified during the period
# of contracts | contract	1		1
Pre-modification recorded investment	$ 427,000		$ 427,000
Post-modification recorded investment	$ 424,000		$ 424,000
HAMP
Troubled debt restructurings - modified during the period
# of contracts | contract	1		1
Pre-modification recorded investment	$ 26,000		$ 26,000
Post-modification recorded investment	26,000		$ 26,000
Real estate - commercial
Troubled debt restructurings - modified during the period
# of contracts | contract			1
Pre-modification recorded investment			$ 110,000
Post-modification recorded investment			52,000
Real estate - commercial | Owner occupied special purpose
Other information
Total Past Due	891,000		891,000		226,000
Real estate - commercial | Owner occupied general purpose
Other information
Total Past Due	1,022,000		1,022,000		1,136,000
Real estate - commercial | Non-owner occupied general purpose
Other information
Total Past Due	$ 3,768,000		$ 3,768,000		593,000
Real estate - residential | Other
Troubled debt restructurings - modified during the period
# of contracts | contract	1		1
Pre-modification recorded investment	$ 34,000		$ 34,000
Post-modification recorded investment	$ 29,000		$ 29,000
Real estate - residential | HAMP
Troubled debt restructurings - modified during the period
# of contracts | contract	1		3
Pre-modification recorded investment	$ 211,000		$ 383,000
Post-modification recorded investment	211,000		$ 331,000
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	952,000		952,000
Real estate - residential | Owner occupied
Other information
Total Past Due	$ 916,000		$ 916,000		74,000
Real estate - residential | Revolving and junior liens | Other
Troubled debt restructurings - modified during the period
# of contracts | contract	2		9
Pre-modification recorded investment	$ 93,000	$ 155,000	$ 596,000	399,000
Post-modification recorded investment	92,000	$ 147,000	587,000	$ 388,000
TDR's defaulted
# of contracts | contract		2		6
Commercial
Other information
Total Past Due	1,080,000		1,080,000		1,270,000
90 Days or Greater Past Due
Other information
Total Past Due	79,000		79,000		$ 248,000
90 Days or Greater Past Due | Commercial
Other information
Total Past Due	$ 6,000		$ 6,000

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