CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Treasury Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive (Loss) Income
Beginning balance (in shares) at Dec. 31, 2012		124.2	9.9
Beginning balance at Dec. 31, 2012	$ 1,467.1	$ 124.2	$ (749.9)	$ 489.0	$ 1,641.7	$ (37.9)
Increase (Decrease) in Stockholders' Equity
Net income	389.1				389.1
Other comprehensive income (loss), net of tax	10.3					10.3
Common stock issued under equity plans, including tax benefits (in shares)		1.8
Common stock issued under equity plans, including tax benefits	127.5	$ 1.8		125.7
Stock-based compensation expense	47.4			47.4
Purchases of treasury stock (in shares)			6.8
Purchases of treasury stock	(497.0)		$ (506.1)	9.1
Ending balance (in shares) at Dec. 31, 2013		126.0	16.7
Ending balance at Dec. 31, 2013	1,544.4	$ 126.0	$ (1,256.0)	671.2	2,030.8	(27.6)
Increase (Decrease) in Stockholders' Equity
Net income	811.1				811.1
Other comprehensive income (loss), net of tax	(73.3)					(73.3)
Common stock issued under equity plans, including tax benefits (in shares)		2.9
Common stock issued under equity plans, including tax benefits	161.8	$ 2.9		158.9
Stock-based compensation expense	48.3			48.3
Purchases of treasury stock (in shares)			4.4
Purchases of treasury stock	(300.9)		$ (300.9)
Ending balance (in shares) at Dec. 31, 2014		128.9	21.1
Ending balance at Dec. 31, 2014	2,191.4	$ 128.9	$ (1,556.9)	878.4	2,841.9	(100.9)
Increase (Decrease) in Stockholders' Equity
Net income	494.9				494.9
Other comprehensive income (loss), net of tax	(81.7)					(81.7)
Common stock issued under equity plans, including tax benefits (in shares)		2.0
Common stock issued under equity plans, including tax benefits	128.7	$ 2.0		126.7
Stock-based compensation expense	49.9			49.9
Purchases of treasury stock (in shares)			2.6
Purchases of treasury stock	(280.1)		$ (280.1)
Stock issued to effect stock split (in shares)		108.2
Stock issued to effect stock split	0.0	$ 108.2		(108.2)
Ending balance (in shares) at Dec. 31, 2015		239.1	23.7
Ending balance at Dec. 31, 2015	$ 2,503.1	$ 239.1	$ (1,837.0)	$ 946.8	$ 3,336.8	$ (182.6)