Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2017

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

Components of the Company’s stock-based compensation expense

The following table summarizes the components of stock-based compensation expense included in general and administrative expenses in the Consolidated Statements of Comprehensive Income:

	Three months ended September 30,						Nine months ended September 30,
	2017			2016			2017			2016
	(In millions)
Total stock-based compensation expense:
Equity classified awards expense	$	1.3		$	2.6		$	9.0		$	8.3
Liability classified awards expense	—			(0.5		)	(1.1		)	0.6
Total pre-tax stock-based compensation expense	1.3			2.1			7.9			8.9
Book income tax benefit	(0.5		)	(0.7		)	(3.0		)	(3.3		)
Total stock-based compensation expense, net of tax	$	0.8		$	1.4		$	4.9		$	5.6

Schedule of stock option valuation assumptions

The following summarizes the assumptions used in the Black-Scholes model:

Risk-free interest rate	1.9	%
Weighted average historical volatility	22.9	%
Dividend yield	7.3	%
Expected years until exercise	4.5
Weighted average fair value of options granted	$4.31

The following summarizes the assumptions used in estimating the fair values:

Risk-free interest rate	1.6	%
Weighted average historical volatility	30.0	%
Dividend yield	9.6	%
Expected years until exercise	3.4
Weighted average fair value of options granted	$3.07
Weighted average fair value of restricted stock units granted	$10.19

Schedule of stock option activity

Stock option balances at September 30, 2017, and activity for the nine months ended September 30, 2017 were as follows:

	Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (in Years)	Aggregate Intrinsic Value (in Millions)
Outstanding at December 31, 2016	701,134		$	80.04
Granted	887,030		48.35
Exercised	(64,916	)	40.59
Expired	(58,217	)	84.43
Forfeited	(171,847	)	65.82
Outstanding at September 30, 2017	1,293,184		61.98		7.3	$	0.9
Vested at September 30, 2017 and Expected to Vest	1,111,610		64.50		7.0	$	0.6
Exercisable at September 30, 2017	456,308		$	81.35	3.3	$	0.0

Schedule of restricted stock unit activity

Outstanding balances as of September 30, 2017, and activity related to restricted stock and restricted stock units for the nine months ended September 30, 2017 were as follows:

	Restricted Stock		Weighted Average Grant Date Fair Value		Restricted Stock Units		Weighted Average Grant Date Fair Value
Outstanding at December 31, 2016	235,472		$	92.81	34,058		$	93.95
Granted	208,460		52.08		275,578		22.37
Released	(89,911	)	88.65		(12,683	)	81.63
Forfeited	(73,409	)	79.44		—		—
Outstanding at September 30, 2017	280,612		$	67.38	296,953		$	28.39