Deposit Accounts - Interest Expense on Deposit Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Interest expense on deposit accounts
Checking accounts	$ 3,295	$ 2,340	$ 1,167
Money market accounts	19,903	28,279	19,567
Savings	393	382	357
Certificates of deposit accounts	10,745	27,296	16,562
Total	$ 34,336	$ 58,297	$ 37,653