Significant Accounting Policies (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loan servicing fees	$ 345
Loan servicing fees, percent of total revenue	0.40%
Earnings on bank-owned life insurance	$ 611	$ 625	$ 336
Earnings on bank-owned life insurance, percent of total revenue	0.70%
Net gain from sales of loans	$ 3,000
Net gain from sales of loans, percent of total revenue	3.30%
Other income, accounted for under other applicable GAAP	$ 1,100
Other income, accounted for under other applicable GAAP, percent of total revenue	1.30%
Core Deposits | Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Weighted average useful life (in years)	6 years
Core Deposits | Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Weighted average useful life (in years)	10 years
Deposit accounts
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue	$ 1,300
Percentage of revenue	1.50%
Debit card
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue	$ 1,000
Percentage of revenue	1.20%
Other
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue	$ 300
Percentage of revenue	0.30%