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Loans - TDR (Details)	3 Months Ended			9 Months Ended
	Sep. 30, 2017 USD ($) contract	Sep. 30, 2016 USD ($) contract	Mar. 31, 2016 USD ($) contract	Sep. 30, 2017 USD ($) contract	Sep. 30, 2016 USD ($) contract	Dec. 31, 2016 USD ($)
Troubled debt restructurings - modified during the period
# of contracts | contract	4			10	8
Pre-modification recorded investment	$ 176,000	$ 70,000		$ 575,000	$ 1,090,000
Post-modification recorded investment	157,000	$ 70,000		542,000	949,000
TDR's defaulted
# of contracts | contract		1
Pre-modification outstanding recorded investment during the period				0	$ 0
Other information
Total Past Due	4,466,000			4,466,000		$ 5,139,000
Real estate - commercial | Other
Troubled debt restructurings - modified during the period
# of contracts | contract					2
Pre-modification recorded investment					$ 312,000
Post-modification recorded investment					$ 211,000
Real estate - commercial | Owner occupied special purpose
Other information
Total Past Due	513,000			513,000
Real estate - commercial | Owner occupied general purpose
Other information
Total Past Due	790,000			790,000		758,000
Real estate - commercial | Non-owner occupied general purpose
Other information
Total Past Due	649,000			649,000		1,046,000
Real estate - residential | Investor
Other information
Total Past Due						237,000
Real estate - residential | Owner occupied
Other information
Total Past Due	$ 40,000			$ 40,000		274,000
Real estate - residential | Owner occupied | Other
Troubled debt restructurings - modified during the period
# of contracts | contract	1			1
Pre-modification recorded investment	$ 42,000			$ 42,000
Post-modification recorded investment	$ 42,000			$ 42,000
Real estate - residential | Owner occupied | HAMP
Troubled debt restructurings - modified during the period
# of contracts | contract	1			1	1
Pre-modification recorded investment	$ 36,000			$ 36,000	$ 239,000
Post-modification recorded investment	33,000			33,000	$ 235,000
Real estate - residential | Revolving and junior liens
Other information
Total Past Due	$ 854,000			$ 854,000		630,000
Real estate - residential | Revolving and junior liens | Other
Troubled debt restructurings - modified during the period
# of contracts | contract	1		1	7	1
Pre-modification recorded investment	$ 49,000		$ 70,000	$ 448,000	$ 70,000
Post-modification recorded investment	$ 33,000		$ 70,000	$ 418,000	$ 70,000
Real estate - residential | Revolving and junior liens | HAMP
Troubled debt restructurings - modified during the period
# of contracts | contract	1			1	4
Pre-modification recorded investment	$ 49,000			$ 49,000	$ 469,000
Post-modification recorded investment	49,000			49,000	$ 433,000
Commercial
Other information
Total Past Due	89,000			89,000		$ 131,000
90 Days or Greater Past Due
Other information
Total Past Due	1,169,000			1,169,000
90 Days or Greater Past Due | Real estate - commercial | Owner occupied general purpose
Other information
Total Past Due	537,000			537,000
90 Days or Greater Past Due | Real estate - residential | Revolving and junior liens
Other information
Total Past Due	$ 100,000			$ 100,000

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