Derivatives - Derivatives Designated as Cash Flow Hedges (Details)	12 Months Ended
	Dec. 31, 2017 USD ($) derivative_instrument
Derivative [Line Items]
Notional Amount	$ 9,886,000
Designated as Hedging Instrument | Interest Rate Swap One
Derivative [Line Items]
Number of positions | derivative_instrument	1
Notional Amount	$ 5,155,000
Asset	0
Liability	$ 81,000
Receive Rate (as a percent)	1.36%
Pay Rate (as a percent)	2.59%
Life (in years)	2 years 10 months 23 days
Designated as Hedging Instrument | Interest Rate Swap Two
Derivative [Line Items]
Number of positions | derivative_instrument	1
Notional Amount	$ 10,000,000
Asset	29,000
Liability	$ 0
Receive Rate (as a percent)	1.49%
Pay Rate (as a percent)	1.43%
Life (in years)	10 months 26 days