Note 12. Accumulated Other Comprehensive Income Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification from AOCI, Current Period, Tax	$ 1.9	$ 1.1
Accumulated Other Comprehensive Income (Loss), Net of Tax	(153.1)	(116.8)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	2,378.9	2,562.0	$ 4,858.0	$ 4,311.1
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(43.0)	(19.1)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	8.0	5.9
Other Comprehensive Income (Loss), Net of Tax	35.0	13.2	(11.3)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(36.3)	(14.6)
Stockholders' Equity Note, Spinoff Transaction		(1,732.2)
Cumulative Effect of New Accounting Principle in Period of Adoption		(18.7)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification from AOCI, Current Period, Tax	0.0	0.0
Accumulated Other Comprehensive Income (Loss), Net of Tax	(1.3)	(1.3)	(22.4)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	0.0	0.0
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0.0	0.0
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	0.0	0.0
Stockholders' Equity Note, Spinoff Transaction		21.3
Cumulative Effect of New Accounting Principle in Period of Adoption		(0.2)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification from AOCI, Current Period, Tax	0.8	0.0
Accumulated Other Comprehensive Income (Loss), Net of Tax	(17.9)	(8.3)	0.3
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(12.8)	(9.6)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	4.5	2.3
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(9.6)	(8.7)
Cumulative Effect of New Accounting Principle in Period of Adoption		0.1
Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification from AOCI, Current Period, Tax	1.1	1.1
Accumulated Other Comprehensive Income (Loss), Net of Tax		(107.2)	(82.7)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(133.9)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(30.2)	(9.5)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	3.5	3.6
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(26.7)	(5.9)
Cumulative Effect of New Accounting Principle in Period of Adoption		(18.6)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Noncontrolling Interest [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Net of Tax	(1.3)	(1.4)
Noncontrolling Interest [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	348.8	351.2	356.9	392.6
Other Comprehensive Income (Loss), Net of Tax	(1.3)	(1.4)	(2.6)
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(153.1)	(116.8)	(104.8)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(153.1)	(116.8)	(104.8)	$ (113.5)
Other Comprehensive Income (Loss), Net of Tax	$ 36.3	14.6	$ (8.7)
Stockholders' Equity Note, Spinoff Transaction		$ 21.3