Consolidated Statements Of Stockholders' Equity - USD ($) $ in Millions	Total	COMMON STOCK, $1 PAR VALUE:	ADDITIONAL PAID-IN CAPITAL:	TREASURY STOCK, AT COST:	RETAINED EARNINGS:	ACCUMULATED OTHER COMPREHENSIVE LOSS:
Beginning balance at Dec. 31, 2014		$ 355.2	$ 156.7	$ (42.7)	$ 6,863.8	$ (579.8)
Net income	$ 1,604.0				1,604.0
Purchases, shares: 2017 - nil; 2016 - 1.38; 2015 - 3.85				(201.6)
Other comprehensive income (loss)	(437.2)					(437.2)
Cash dividends declared on common stock, per share: 2017 - $2.19; 2016 - $1.56; 2015 - $2.32					(819.8)
Treasury stock retirement		(4.6)	(128.5)	244.3	(111.2)
Stock compensation		0.7
Stock compensation and tax benefit			41.1
Ending balance at Dec. 31, 2015	6,940.4	351.3	69.3		7,536.8	(1,017.0)
Net income	521.7				521.7
Purchases, shares: 2017 - nil; 2016 - 1.38; 2015 - 3.85				(70.5)
Other comprehensive income (loss)	(111.1)					(111.1)
Cash dividends declared on common stock, per share: 2017 - $2.19; 2016 - $1.56; 2015 - $2.32					(547.9)
Treasury stock retirement		(1.4)	(43.4)	$ 70.5	(25.7)
Stock compensation		0.8
Stock compensation and tax benefit			44.2
Ending balance at Dec. 31, 2016	6,777.6	350.7	70.1		7,484.9	(1,128.1)
Net income	1,675.2				1,675.2
Other comprehensive income (loss)	334.5					334.5
Cash dividends declared on common stock, per share: 2017 - $2.19; 2016 - $1.56; 2015 - $2.32					(771.1)
Stock compensation		1.1
Stock compensation and tax benefit			53.1
Cumulative effect of change in accounting principle					(19.9)
Ending balance at Dec. 31, 2017	$ 8,050.5	$ 351.8	$ 123.2		$ 8,369.1	$ (793.6)