Note 12. Accumulated Other Comprehensive Income Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	$ (30.9)	$ (153.1)
Other comprehensive loss, net of tax, before reclassifications	(11.7)	(43.0)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	18.5	8.0
Settlement of pension plan, net of tax benefit of $34.9, $—, and $—	116.6	0.0	$ 0.0
Other Comprehensive Income (Loss), Net of Tax	(123.4)	35.0	13.2
Other comprehensive loss	122.2	(36.3)
Reclassification from AOCI, Current Period, Tax	5.1	(1.9)
Other Comprehensive Income (Loss), Defined Benefit Plan, Adjustment for Settlement or Curtailment Gain (Loss), Tax	34.9	0.0	0.0
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	(1.3)	(1.3)	(1.3)
Other comprehensive loss, net of tax, before reclassifications	0.0	0.0
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0.0	0.0
Settlement of pension plan, net of tax benefit of $34.9, $—, and $—	0.0
Other comprehensive loss	0.0	0.0
Reclassification from AOCI, Current Period, Tax	0.0	0.0
Other Comprehensive Income (Loss), Defined Benefit Plan, Adjustment for Settlement or Curtailment Gain (Loss), Tax	0.0
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	(25.6)	(17.9)	(8.3)
Other comprehensive loss, net of tax, before reclassifications	(19.4)	(12.8)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	12.9	4.5
Settlement of pension plan, net of tax benefit of $34.9, $—, and $—	0.0
Other comprehensive loss	(7.7)	(9.6)
Reclassification from AOCI, Current Period, Tax	3.5	(0.8)
Other Comprehensive Income (Loss), Defined Benefit Plan, Adjustment for Settlement or Curtailment Gain (Loss), Tax	0.0
Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	(4.0)	(133.9)	(107.2)
Other comprehensive loss, net of tax, before reclassifications	7.7	(30.2)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	5.6	3.5
Settlement of pension plan, net of tax benefit of $34.9, $—, and $—	116.6
Other comprehensive loss	129.9	(26.7)
Reclassification from AOCI, Current Period, Tax	1.6	(1.1)
Other Comprehensive Income (Loss), Defined Benefit Plan, Adjustment for Settlement or Curtailment Gain (Loss), Tax	34.9
Accumulated Gain (Loss), Net, Cash Flow Hedge, Noncontrolling Interest [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Net of Tax	(1.2)	(1.3)
Noncontrolling Interest [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Net of Tax	(1.2)	(1.3)	(1.4)
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	(30.9)	(153.1)	(116.8)
Other Comprehensive Income (Loss), Net of Tax	$ (122.2)	$ 36.3	$ 14.6