Share-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2015

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Summary of Expense Related to Share-Based Compensation Cost by Type of Program

A summary of the expense related to share-based compensation cost by type of program is as follows:

	Year Ended December 31,
(In millions)	2015			2014			2013
Restricted stock units expense	$	10.2		$	16.5		$	10.6
Stock options expense		—			0.5			1.0
Before-tax share-based compensation expense		10.2			17.0			11.6
Income tax benefit		(3.3	)		(6.0	)		(3.9	)
After-tax share-based compensation expense	$	6.9		$	11.0		$	7.7

Summary of Stock Option Activity Under All Plans

A summary of stock option activity under all plans as of and for the year ended December 31, 2015 is as follows:

	Shares			Weighted Average Remaining Contractual Terms (Years)		Weighted Average Exercise Price		Aggregate Intrinsic Value (In millions)
Outstanding on January 1, 2015		289,064				$	116.40
Granted		—					—
Exercised		(17,324	)				31.72
Expired		(3,129	)				1,183.96
Outstanding on December 31, 2015		268,611			4.4 years	$	109.42	$	—
Vested as of December 31, 2015		268,611			4.4 years	$	109.42	$	—
Expected to vest as of December 31, 2015		—			0.0 years	$	—	$	—

Summary of Information about Stock Options Outstanding by Range of Exercise Prices

The following table summarizes information about stock options outstanding at December 31, 2015:

	Outstanding						Exercisable
Range of Exercise Prices	Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Life		Shares		Weighted Average Exercise Price
$8.74 to $25.00		38,572	$	21.25		3.2 years		38,572	$	21.25
$25.01 to $41.50		173,989		33.87		5.6 years		173,989		33.87
$75.00 to $476.00		24,998		172.47		2.1 years		24,998		172.47
$476.01 to $1,334.50		31,052		591.52		0.8 years		31,052		591.52
$8.74 to $1,344.50		268,611		109.42		4.4 years		268,611		109.42

Summary of Restricted Stock Unit Activity Under All Plans

A summary of restricted stock unit activity under all plans as of and for the year ended December 31, 2015 is as follows:

	Shares			Weighted Average Remaining Contractual Terms (Years)		Weighted Average Grant Date Fair Value		Aggregate Intrinsic Value (In millions)
Outstanding on January 1, 2015		972,843				$	41.30
Granted		519,852					36.15
Vested and released		(495,337	)				37.43
Forfeited		(427,260	)				42.40
Outstanding on December 31, 2015		570,098			1.2 Years	$	40.55	$	9.1
Vested or expected to vest as of December 31, 2015		596,048			1.2 Years	$	41.01	$	10.8
Expected to vest as of December 31, 2015		576,378			1.2 Years	$	40.56	$	8.9

Weighted Average Assumptions Used in Monte Carlo Simulation Model to Estimate Fair Value of PRSUs Granted

The weighted averages for the primary assumptions used in the Monte Carlo simulation model for the 2015 and 2014 grants are as follows:

	PRSU Grants
	Year Ended December 31,
	2015			2014
Assumptions:
Risk-free interest rate		1.01	%		0.79	%
Expected life		3.0 years			3.0 years
Expected volatility		37	%		43	%