Capital Stock (Tables)

12 Months Ended

Dec. 31, 2018

Equity [Abstract]

Schedule of earnings per share

Earnings per share for the years ended December 31, 2018, 2017 and 2016 respectively, are computed as follows:

	For the Year Ended
	December 31, 2018		December 31, 2017		December 31, 2016
	(dollars in thousands)
Numerator:
Net income available to common shareholders	$	368,440	$	491,184	$	549,494
Effect of dilutive securities:	—		—		—
Dilutive net income available to common shareholders	$	368,440	$	491,184	$	549,494
Denominator:
Weighted average basic shares	187,146,170		187,780,355		187,728,634
Effect of dilutive securities	602,692		506,965		296,204
Weighted average dilutive shares	187,748,862		188,287,320		188,024,838
Net income per average share attributable to common stockholders - Basic	$	1.97	$	2.62	$	2.93
Net income per average share attributable to common stockholders - Diluted	$	1.96	$	2.61	$	2.92