Earnings Per Common Share (Tables)

6 Months Ended

Jun. 30, 2018

Earnings Per Share [Abstract]

Net Income, Weighted Average Common Shares Used in Calculating Basic Earnings Per Common Share and Diluted EPS

The following table presents net income, the weighted average common shares used in calculating basic earnings per common share (“EPS”) and those used in calculating diluted EPS for each period presented below. Diluted EPS reflects the incremental common shares from: (1) shares issuable upon vesting of PSUs and ESPP using the treasury stock method; and (2) shares issuable upon conversion of the MCPS using the if-converted method. Refer to Note 14 - Stock Based Compensation

and Note 15 - Equity Transactions for further information regarding potential common share issuances. The outstanding RSUs have non-forfeitable rights to dividend equivalents and are therefore included in calculating basic and diluted EPS under the two-class method.

	Three Months Ended   June 30,						Six Months Ended   June 30,
	2018			2017			2018			2017
Numerator
Net income	$	67.0		$	120.2		$	173.0		$	264.0
Less: Preferred stock dividends	(4.8		)	—			(4.8		)	—
Net income attributable to common stockholders	62.2			120.2			168.2			264.0
Less: Common stock dividends paid	(30.9		)	(30.3		)	(60.6		)	(60.0		)
Undistributed earnings	$	31.3		$	89.9		$	107.6		$	204.0
Denominator
Weighted average shares outstanding used in basic   earnings per share	57,060,313			55,230,367			55,125,584			55,713,172
Incremental common shares from:
PSUs	163,596			239,400			217,455			321,849
ESPP	40,499			40,131			40,499			40,131
MCPS	—			—			1,889,890			—
Weighted average shares used in diluted earnings per   share calculations	57,264,408			55,509,898			57,273,428			56,075,152
Earnings per common share - Basic
Distributed earnings	$	0.54		$	0.55		$	1.10		$	1.08
Undistributed earnings	0.55			1.63			1.95			3.66
Net income attributable to common stockholders	$	1.09		$	2.18		$	3.05		$	4.74
Earnings per common share - Diluted
Distributed earnings	$	0.54		$	0.54		$	1.06		$	1.07
Undistributed earnings	0.55			1.62			1.96			3.64
Net income attributable to common stockholders	$	1.09		$	2.16		$	3.02		$	4.71