Consolidated Statements of Stockholders' Equity - USD ($) $ in Millions	Total	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Parent [Member]	Noncontrolling Interest [Member]
Beginning balance at Dec. 31, 2014	$ 1,854.9	$ 288.7	$ (493.1)	$ 739.0	$ 2,111.2	$ (794.4)	$ 1,851.4	$ 3.5
Comprehensive income	310.6				350.0	(39.4)	310.6
Cash dividends on common stock	(206.3)				(206.3)		(206.3)
Stock-based compensation and other	47.6	3.3	(30.0)	74.2	0.1		47.6
Common stock purchased and retired	(180.4)	(4.5)		(11.8)	(164.1)		(180.4)
Ending balance at Dec. 31, 2015	1,826.4	287.5	(523.1)	801.4	2,090.9	(833.8)	1,822.9	3.5
Comprehensive income	316.8				527.8	(211.0)	316.8
Cash dividends on common stock	(328.6)				(328.6)		(328.6)
Stock-based compensation and other	89.5	3.4	(22.2)	76.4	(0.2)		57.4	32.1
Common stock purchased and retired	9,480.3	213.9		9,266.4			9,480.3
Ending balance at Dec. 31, 2016	11,384.4	504.8	(545.3)	10,144.2	2,289.9	(1,044.8)	11,348.8	35.6
Comprehensive income	3,030.5				2,748.8	281.7	3,030.5
Cash dividends on common stock	(427.5)				(427.5)		(427.5)
Stock-based compensation and other	346.3	8.3	(28.2)	365.2			345.3	1.0
Common stock purchased and retired	(152.4)	(5.0)		(147.4)			(152.4)
Ending balance at Dec. 31, 2017	$ 14,181.3	$ 508.1	$ (573.5)	$ 10,362.0	$ 4,611.2	$ (763.1)	$ 14,144.7	$ 36.6

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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