Income Taxes - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating Loss Carryforwards
Temporary differences related to provision for loan losses not expected to reverse therefore not included in deferred tax assets	$ 4
Total state net operating loss carryforwards	393
Valuation allowance	7	$ 5
Maximum
Operating Loss Carryforwards
Income tax penalties and interest expense (less than)	1	1	$ 1
Federal
Operating Loss Carryforwards
Operating loss carryforwards	51	$ 68
State and Local Jurisdiction
Operating Loss Carryforwards
Total state deferred tax asset	28
Operating loss carryforwards, amount subject to annual use limitation	21
Valuation allowance	$ 7