Business Combinations - Due Diligence, Merger-related and Merger Integration Expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Business Combinations [Abstract]
Advertising	$ 0	$ 0	$ 61
Employee Benefits	0	0	271
Occupancy and bank premises	0	0	2,145
Furniture, fixtures, and equipment	0	0	365
Data processing	0	0	421
Professional fees	0	0	1,450
Salaries and wages	0	0	852
Other	0	0	2,196
Total due diligence, merger-related and merger integration expenses	$ 0	$ 0	$ 7,761