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Loans - TDR (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2018 USD ($) contract	Jun. 30, 2017 USD ($) contract	Jun. 30, 2018 USD ($) contract	Jun. 30, 2017 USD ($) contract	Dec. 31, 2017 USD ($)
Troubled debt restructurings - modified during the period
# of contracts | contract	5		10
Pre-modification recorded investment	$ 464,000.000	$ 155,000	$ 706,000	$ 399,000
Post-modification recorded investment	382,000.000	$ 147,000	622,000	$ 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	$ 10,509,000		$ 10,509,000		$ 5,606,000
Real estate - commercial
Troubled debt restructurings - modified during the period
# of contracts | contract	1		1
Pre-modification recorded investment	$ 110,000.000		$ 110,000
Post-modification recorded investment	56,000.000		56,000
Real estate - commercial | Owner occupied special purpose
Other information
Total Past Due	1,981,000		1,981,000		226,000
Real estate - commercial | Owner occupied general purpose
Other information
Total Past Due	1,353,000		1,353,000		1,136,000
Real estate - commercial | Non-owner occupied general purpose
Other information
Total Past Due	$ 3,456,000		$ 3,456,000		593,000
Real estate - residential | HAMP
Troubled debt restructurings - modified during the period
# of contracts | contract	1		1
Pre-modification recorded investment	$ 49,000.000		$ 49,000
Post-modification recorded investment	39,000.000		$ 39,000
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	612,000		612,000
Real estate - residential | Owner occupied
Other information
Total Past Due	$ 918,000		$ 918,000		74,000
Real estate - residential | Revolving and junior liens | Other
Troubled debt restructurings - modified during the period
# of contracts | contract	3		7
Pre-modification recorded investment	$ 305,000.000	$ 155,000	$ 523,000	399,000
Post-modification recorded investment	287,000.000	$ 147,000	503,000	$ 388,000
TDR's defaulted
# of contracts | contract		2		6
Commercial
Other information
Total Past Due	210,000		210,000		1,270,000
90 Days or Greater Past Due
Other information
Total Past Due	1,153,000		1,153,000		$ 248,000
90 Days or Greater Past Due | Real estate - commercial | Owner occupied general purpose
Other information
Total Past Due	450,000		450,000
90 Days or Greater Past Due | Real estate - commercial | Non-owner occupied general purpose
Other information
Total Past Due	174,000		174,000
90 Days or Greater Past Due | Real estate - residential | Investor
Other information
Total Past Due	$ 38,000		$ 38,000

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