Disclosures About Fair Value of Assets and Liabilities - Reconciliation of Beginning and Ending Balances of Recurring Fair Value Measurements using Significant Unobservable Level 3 Inputs (Details) - Fair Value, Measurements, Recurring - Available for Sale Securities - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Available for Sale Securities
Balance at beginning of the period	$ 3,970	$ 3,330	$ 3,978	$ 5,169
Included in other comprehensive income	(35)	(22)	(59)	38
Principal payments	(620)	679	(604)	(1,220)
Ending balance	$ 3,315	$ 3,987	$ 3,315	$ 3,987