Note 9. Employee Benefit Plans Changes in Benefit Obligations and Plan Assets Table (Details) - Defined Benefit Pension Plan - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Net Periodic Benefit Cost
Net periodic pension cost	$ 1	$ 1
Interest cost	5	6
Actuarial loss	2	2
Expected return on plan assets	(7)	(7)
Benefit Obligations
Defined Benefit Plan, Benefit Obligation	128	145
Fair value of plan assets	90	108
Underfunded at end of year	$ 38	$ 37