STATEMENTS OF CONSOLIDATED SHAREHOLDERS' EQUITY - USD ($)	Total	Accounting Standards Update 2014-09 [Member]	Accounting Standards Update 2016-06	Accounting Standards Update 2018-02	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Retained Earnings [Member] Accounting Standards Update 2014-09 [Member]	Retained Earnings [Member] Accounting Standards Update 2016-06	Retained Earnings [Member] Accounting Standards Update 2018-02	AOCI Attributable to Parent [Member]	AOCI Attributable to Parent [Member] Accounting Standards Update 2018-02	Treasury Stock [Member]	Noncontrolling Interest [Member]
Common Stock, Shares, Issued					88,457,634
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 1,365,600,000				$ 4,400,000	$ 584,400,000	$ 1,676,200,000				$ (110,000,000.0)		$ (796,800,000)	$ 7,400,000
Stockholders' Equity Attributable to Parent											(110,000,000.0)
Net Income	252,400,000						252,400,000
Net Income (Loss) Attributable to Noncontrolling Interest	(7,400,000)													(7,400,000)
Other comprehensive income (loss)	(3,000,000.0)										(3,000,000.0)
Dividends	51,800,000					600,000	(52,400,000)
Payment, Tax Withholding, Share-based Payment Arrangement	(14,100,000)												(14,100,000)
Payments for Repurchase of Common Stock	0
Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture	27,400,000					27,400,000							56,600,000
Stock Issued During Period, Value, Stock Options Exercised	40,000,000.0					3,600,000							36,400,000
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures	0					(17,300,000)							17,300,000
Stock Issued During Period, Value, Employee Stock Purchase Plan	7,100,000					4,200,000							2,900,000
Common Stock, Shares, Issued					88,457,634
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	1,616,200,000				$ 4,400,000	602,900,000	1,876,200,000				(113,000,000.0)		(754,300,000)	0
Stockholders' Equity Attributable to Parent											(113,000,000.0)
Net Income	152,200,000						152,200,000
Other comprehensive income (loss)	(64,100,000)										$ (64,100,000)
Dividends	(55,400,000)					500,000	(55,900,000)
Payment, Tax Withholding, Share-based Payment Arrangement	(4,700,000)												(4,700,000)
Payments for Repurchase of Common Stock	(117,200,000)												117,200,000
Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture	33,900,000					33,900,000							22,700,000
Stock Issued During Period, Value, Stock Options Exercised	14,500,000					2,600,000							11,900,000
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures	0					(7,700,000)							7,700,000
Stock Issued During Period, Value, Employee Stock Purchase Plan	8,400,000					5,200,000							3,200,000
New Accounting Pronouncement or Change in Accounting Principle, Description of Prior-period Information Retrospectively Adjusted		(4.9)	(5.6)	—							(5.4)
Common Stock, Shares, Issued					88,457,634
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	1,573,300,000				$ 4,400,000	637,400,000	1,967,400,000				$ (182,500,000)		(853,400,000)	0
Stockholders' Equity Attributable to Parent	1,573,300,000							$ (4,900,000)	$ (5,600,000)	$ 5,400,000	(182,500,000)	$ (5,400,000)
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification										$ 5,400,000
Net Income	223,000,000.0						223,000,000.0
Other comprehensive income (loss)	2,300,000
Dividends	58,000,000.0					500,000	(58,500,000)
Payment, Tax Withholding, Share-based Payment Arrangement	(16,500,000)												16,500,000
Payments for Repurchase of Common Stock	(54,100,000)												54,100,000
Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture	37,800,000					37,800,000							26,700,000
Stock Issued During Period, Value, Stock Options Exercised	8,600,000					2,900,000							5,700,000
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures	0					(17,100,000)							17,100,000
Stock Issued During Period, Value, Employee Stock Purchase Plan	9,400,000					5,500,000							3,900,000
Cumulative Effect on Retained Earnings, Net of Tax	$ 300,000
New Accounting Pronouncement or Change in Accounting Principle, Description of Prior-period Information Retrospectively Adjusted								0.3
Common Stock, Shares, Issued	88,457,634				88,457,634
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 1,726,100,000				$ 4,400,000	$ 667,000,000.0	$ 2,132,200,000				(180,200,000)		$ (897,300,000)	$ 0
Stockholders' Equity Attributable to Parent	$ 1,726,100,000										$ (180,200,000)