Lease - Supplemental balance sheet information (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Finance leases:
Premises and equipment	$ 7,780	$ 7,780
Accumulated depreciation	(4,326)	(4,178)
Premises and equipment, net	$ 3,454	$ 3,602
Financial position	us-gaap:PropertyPlantAndEquipmentNet	us-gaap:PropertyPlantAndEquipmentNet