Loans and Loans Held for Sale - Summary of Aggregate Amount of Loans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Loans Receivable from Officers and Directors [Roll Forward]
Balance at beginning of year	$ 10,070	$ 25,167
New loans	2,841	25,203
Repayments or no longer considered a related party	(4,229)	(40,300)
Balance at end of year	$ 8,682	$ 10,070