Capital Stock (Tables)

12 Months Ended

Dec. 31, 2016

Equity [Abstract]

Schedule of Earnings Per Share

Earnings per share for the years ended December 31, 2016, 2015, and 2014 respectively, are computed as follows:

	For the Year Ended
	December 31, 2016		December 31, 2015		December 31, 2014
	(dollars in thousands)
Numerator:
Net income available to common shareholders	$	549,494	$	250,349	$	589,205
Effect of dilutive securities:	—		—		—
Dilutive net income available to common shareholders	$	549,494	$	250,349	$	589,205
Denominator:
Weighted average basic shares	187,728,634		199,563,196		205,450,095
Effect of dilutive securities	296,204		86,981		58,674
Weighted average dilutive shares	188,024,838		199,650,177		205,508,769
Net income per average share attributable to common stockholders - Basic	$	2.93	$	1.25	$	2.87
Net income per average share attributable to common stockholders - Diluted	$	2.92	$	1.25	$	2.87