Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Millions	Total	Common Stock	Treasury Stock	Additional Paid in Capital	Retained Earnings	Accumulated Other Comprehensive Loss
Beginning Balance (in shares) at Dec. 31, 2012		98,143,000	0
Beginning Balance at Dec. 31, 2012	$ 1,008.3	$ 1.0	$ 0.0	$ 378.8	$ 742.5	$ (114.0)
Common stock repurchases and retirements (in shares)	(171,263)	(171,000)	0
Common stock repurchases and retirements	$ (7.8)	$ 0.0	$ 0.0	(1.1)	(6.7)	0.0
Common stock withheld and retired to cover taxes on vested stock awards (in shares)		(224,000)	0
Common stock withheld and retired to cover taxes on vested stock awards	(11.0)	$ 0.0	$ 0.0	(1.4)	(9.6)	0.0
Common stock dividends declared	(148.4)	$ 0.0	$ 0.0	0.0	(148.4)	0.0
Restricted stock grants and cancellations (in shares)		297,000	0
Restricted stock grants and cancellations	6.9	$ 0.0	$ 0.0	6.9	0.0	0.0
Exercise of stock options (in shares)		127,000	0
Exercise of stock options	3.7	$ 0.0	$ 0.0	3.7	0.0	0.0
Share-based compensation expense	14.8	0.0	0.0	14.8	0.0	0.0
Comprehensive income	490.3	$ 0.0	$ 0.0	0.0	441.3	49.0
Ending Balance (in shares) at Dec. 31, 2013		98,172,000	0
Ending Balance at Dec. 31, 2013	$ 1,356.8	$ 1.0	$ 0.0	401.7	1,019.1	(65.0)
Common stock repurchases and retirements (in shares)	0
Common stock repurchases and retirements	$ 0.0
Common stock withheld and retired to cover taxes on vested stock awards (in shares)		(183,000)	0
Common stock withheld and retired to cover taxes on vested stock awards	(13.2)	$ 0.0	$ 0.0	(1.2)	(12.0)	0.0
Common stock dividends declared	(157.5)	$ 0.0	$ 0.0	0.0	(157.5)	0.0
Restricted stock grants and cancellations (in shares)		228,000	0
Restricted stock grants and cancellations	9.7	$ 0.0	$ 0.0	9.7	0.0	0.0
Exercise of stock options (in shares)		151,000	0
Exercise of stock options	6.3	$ 0.0	$ 0.0	6.3	0.0	0.0
Share-based compensation expense	15.6	0.0	0.0	15.6	0.0	0.0
Comprehensive income	303.7	$ 0.0	$ 0.0	0.0	392.6	(88.9)
Ending Balance (in shares) at Dec. 31, 2014		98,368,000	0
Ending Balance at Dec. 31, 2014	$ 1,521.4	$ 1.0	$ 0.0	432.1	1,242.2	(153.9)
Common stock repurchases and retirements (in shares)	(2,326,493)	(2,326,000)	0
Common stock repurchases and retirements	$ (154.7)	$ 0.0	$ 0.0	(15.6)	(139.1)	0.0
Common stock withheld and retired to cover taxes on vested stock awards (in shares)		(131,000)	0
Common stock withheld and retired to cover taxes on vested stock awards	(8.7)	$ 0.0	$ 0.0	(0.8)	(7.9)	0.0
Common stock dividends declared	(214.7)	$ 0.0	$ 0.0	0.0	(214.7)	0.0
Restricted stock grants and cancellations (in shares)		218,000	0
Restricted stock grants and cancellations	6.0	$ 0.0	$ 0.0	6.0	0.0	0.0
Share-based compensation expense	18.2	0.0	0.0	18.2	0.0	0.0
Comprehensive income	465.8	$ 0.0	$ 0.0	0.0	436.8	29.0
Ending Balance (in shares) at Dec. 31, 2015		96,129,000	0
Ending Balance at Dec. 31, 2015	$ 1,633.3	$ 1.0	$ 0.0	$ 439.9	$ 1,317.3	$ (124.9)

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This element represents the amount of recognized equity-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized). Alternate captions include the words "stock-based compensation".

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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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