Loan Servicing Rights - Summary of Loan Servicing Rights (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance, beginning of period	$ 23	$ 25	$ 30
Acquired in the Merger	59,567	0	0
New servicing assets created	4,969	7	4
Impairment (charge) recovery	(3,882)	0	0
Amortization	(4,364)	(9)	(9)
Balance, end of period	56,313	23	25
Valuation allowance, end of period	(3,882)	0	0
Loans serviced for others that have servicing rights capitalized, end of period	$ 6,566,892	$ 0	$ 0