Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2013

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Performance Stock Units

The following table shows a summary of the performance stock units as of September 30, 2013:

Performance Period	Minimum Shares		Target Shares		Maximum Shares
2012 – 2014		0		98,453		147,680
2013 – 2015		0		95,858		143,787

Summary of Status and Activity of Non-Vested Stock Awards

The following table shows a summary of the status and activity of non-vested stock awards for the nine months ended September 30, 2013:

	Restricted Stock Units			Performance Stock Units			Total Stock Units			Weighted Average Grant Date Fair Value per Unit
Non-vested at December 31, 2012		136,098			268,677			404,775		$	36.11
Granted		62,276			97,318			159,594		$	42.64
Credited from dividends		3,526			7,064			10,590		$	35.17
Performance stock unit adjustment		0			43,921			43,921		$	40.09
Vested		(46,314	)		(85,798	)		(132,112	)	$	29.81
Forfeited		(2,059	)		(3,084	)		(5,143	)	$	40.34
Non-vested at September 30, 2013		153,527			328,098			481,625		$	40.29

Stock Options Fair Value Assumptions

In accordance with accounting standards, compensation expense for non-vested stock options is recorded over the vesting period based on the fair value at the date of grant. The fair value of stock options on the date of grant is calculated using the Black-Scholes-Merton model and the assumptions listed below:

	February 2013 Grant			February 2012 Grant			February 2011 Grant
Grant date price per share of option award	$	42.76		$	38.21		$	40.26
Expected dividend yield per share		2.75	%		2.75	%		2.50	%
Expected life in years		6.5			6.5			6.5
Expected volatility		53.77	%		55.06	%		60.00	%
Risk-free interest rate		1.29	%		1.34	%		3.02	%
Grant date fair value per share of option awards	$	17.28		$	15.82		$	19.28

Summary of Status and Activity of Stock Options

The following table shows a summary of the status and activity of stock options for the nine months ended September 30, 2013:

	Options			Weighted Average Exercise Price per Option		Weighted Average Remaining Contractual Term (in years)		Aggregate Intrinsic Value (in millions)
Outstanding at December 31, 2012		331,799		$	34.07
Granted		94,532		$	42.76
Exercised		(5,251	)	$	39.04
Outstanding at September 30, 2013		421,080		$	35.96		7.11	$	2.8
Exercisable at September 30, 2013		167,565		$	29.15		4.94	$	2.3

Schedule of Stock-Based Compensation Expense Recognized

Total stock-based compensation expense recognized for the three and nine months ended September 30, 2013 and 2012 is as follows:

	Three Months Ended September 30,				Nine Months Ended September 30,
	2013		2012		2013		2012
(Dollars in millions)
Stock-based compensation expense recognized:
Selling, general and administrative expenses	$	1.9	$	1.9	$	4.7	$	5.1
Less related income tax benefit		0.8		0.8		1.9		2.0
	$	1.1	$	1.1	$	2.8	$	3.1