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Loans - TDR (Details) $ in Thousands	12 Months Ended		24 Months Ended
	Dec. 31, 2017 USD ($) contract	Dec. 31, 2016 USD ($) contract	Dec. 31, 2017 USD ($) item
Troubled debt restructurings - modified during the period
# of contracts | contract	11	10
Pre-modification recorded investment	$ 690	$ 1,791
Post-modification recorded investment	761	1,472
TDR's defaulted
# of contracts | item			0
Other information
Commitments to lend to borrowers whose loans were classified as impaired	0		$ 0
Total Past Due	$ 5,606	$ 5,139	5,606
Other
Troubled debt restructurings - modified during the period
# of contracts | contract	1	2
Pre-modification recorded investment	$ 97	$ 312
Post-modification recorded investment	131	$ 205
HAMP
Troubled debt restructurings - modified during the period
# of contracts | contract		2
Pre-modification recorded investment		$ 419
Post-modification recorded investment		262
Real estate - commercial | Owner occupied special purpose
Other information
Total Past Due	226		226
Real estate - commercial | Owner occupied general purpose
Other information
Total Past Due	1,136	758	1,136
Real estate - commercial | Non-owner occupied general purpose
Other information
Total Past Due	$ 593	1,046	593
Real estate - residential
Troubled debt restructurings - modified during the period
# of contracts | contract	1
Pre-modification recorded investment	$ 41
Post-modification recorded investment	42
Real estate - residential | Investor
Other information
Total Past Due		237
Real estate - residential | Owner occupied
Other information
Total Past Due	$ 74	274	74
Real estate - residential | Owner occupied | HAMP
Troubled debt restructurings - modified during the period
# of contracts | contract	2
Pre-modification recorded investment	$ 184
Post-modification recorded investment	189
Real estate - residential | Revolving and junior liens
Other information
Total Past Due	$ 769	$ 630	769
Real estate - residential | Revolving and junior liens | Other
Troubled debt restructurings - modified during the period
# of contracts | contract	6	3
Pre-modification recorded investment	$ 319	$ 808
Post-modification recorded investment	$ 350	$ 777
Real estate - residential | Revolving and junior liens | HAMP
Troubled debt restructurings - modified during the period
# of contracts | contract	1	3
Pre-modification recorded investment	$ 49	$ 252
Post-modification recorded investment	49	228
Commercial
Other information
Total Past Due	1,270	$ 131	1,270
90 Days or Greater Past Due
Other information
Total Past Due	248		248
Principal Officers, Directors, and Affiliates | 90 Days or Greater Past Due
Other information
Total Past Due	$ 0		$ 0

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