Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2017

Stockholders' Equity Note [Abstract]

Schedule of Share-based Compensation, Restricted Stock Activity

The following table presents restricted stock activity for the years 2017, 2016 and 2015:



	2017				2016				2015
	# of Shares		Weighted Average Fair Value at Date of Grant		# of Shares		Weighted Average Fair Value at Date of Grant		# of Shares		Weighted Average Fair Value at Date of Grant
Nonvested restricted shares outstanding at January 1	224,289		$	41.30	197,674		$	43.56	366,363		$	38.24
Granted	216,017		36.03		150,647		39.47		107,346		45.34
Forfeited	(29,150	)	42.50		(51,234	)	43.56		(39,322	)	40.93
Vested	(127,818	)	41.06		(72,798	)	42.06		(236,713	)	36.57
Nonvested restricted shares outstanding at December 31	283,338		$	37.26	224,289		$	41.30	197,674		$	43.56

Reconciliation of the Common and Potential Common Shares Outstanding Used in Earnings Per Share Calculation

A reconciliation of the average number of common and potential common shares outstanding used in the calculations of basic and diluted net income per share follows ($ in millions, shares in thousands):



	For the Years Ended December 31,
	2017			2016			2015
Numerator (basic and diluted):
Net income	$	34.5		$	82.8		$	89.7
Less: Dividends paid to participating securities	(0.4		)	(0.3		)	(0.2		)
Less: Undistributed earnings available to participating securities	—			(0.2		)	(0.3		)
Undistributed and distributed earnings available to common stockholders	$	34.1		$	82.3		$	89.2

Denominator:
Average number of common shares outstanding	30,407.1			30,310.9			30,251.4
Effect of dilutive stock-based compensation	142.2			152.5			122.9
Average number of common and potential common shares outstanding	30,549.3			30,463.4			30,374.3