Bank Premises and Equipment Net Book Value (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Bank Premises and Equipment
Total bank premises and equipment	$ 122,324	$ 118,682
Accumulated depreciation	(62,230)	(56,836)
Bank premises and equipment, net	60,094	61,846
Land
Bank Premises and Equipment
Total bank premises and equipment	15,035	15,317
Building and premises
Bank Premises and Equipment
Total bank premises and equipment	74,807	73,097
Furniture, fixtures and equipment
Bank Premises and Equipment
Total bank premises and equipment	$ 32,482	$ 30,268