Amount of cumulative tax effect on beginning retained earnings from change in accounting principle.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 20
-Section 45
-Paragraph 11
-Subparagraph (a)
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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a),(b)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h))
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Stock-Based Compensation - Accounting Standards Update 2016-09 (Details) - USD ($) $ in Millions		12 Months Ended
	Jan. 01, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Stock-Based Compensation
Income tax expense (benefit)		$ 63.7	$ 117.5	$ 23.1
ASU 2016-09 - Stock Compensation
Stock-Based Compensation
Income tax expense (benefit)		$ 1.3	$ 1.9
ASU 2016-09 - Stock Compensation \| Adjustment
Stock-Based Compensation
Cumulative adjustment to retained earnings	$ 3.6