Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2019

Earnings Per Share [Abstract]

Schedule of calculation of pro forma basic and diluted earnings per share

The calculation of basic and diluted earnings per share of common stock for the years ended December 31, 2019, 2018 and 2017 is as follows (dollars in millions, except per share data):

	2019			2018			2017
Numerator:
Net income attributable to controlling interests	$	223.9		$	136.4		$	4.2
Less: Total income available to participating unvested securities(1)	(0.1		)	(0.4		)	(0.2		)
Total net income attributable to common stock	$	223.8		$	136.0		$	4.0
Denominator:
Weighted-average shares of common stock outstanding—basic	91,205,412			107,431,821			110,708,598
Potential shares of common stock
Restricted stock units	63,540			191,371			672,544
Weighted-average shares of common stock outstanding—diluted	91,268,952			107,623,192			111,381,142
Earnings per share of common stock attributable to controlling interests:
Basic	$	2.45		$	1.27		$	0.04
Diluted	$	2.45		$	1.26		$	0.04

(1) Income available to participating unvested securities includes dividends paid on unvested restricted shares and their proportionate share of undistributed earnings.