Derivatives (Details) - Summary of interest rate swap designated as a cash flow hedges - USD ($) $ in Thousands	6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Summary of interest rate swap designated as a cash flow hedges [Abstract]
Notional amount	$ 100,000	$ 100,000	$ 100,000
Weighted average pay rates	1.68%	1.58%	1.66%
Weighted average receive rates	1.99%	1.08%	1.23%
Weighted average maturity	1 year 10 months 25 days	3 years 1 month 6 days	2 years 4 months 24 days
Fair value	$ 1,893	$ 45	$ 798