Earnings Per Share (Tables)

6 Months Ended

Jun. 30, 2018

Earnings Per Share [Abstract]

Schedule of Earnings Per Share, Basic and Diluted

	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2018		2017		2018		2017
	(In thousands, except per share amounts)
Amounts attributable to common stockholders:
Net income:
Net income — basic	$	103,239	$	68,481	$	185,227	$	243,183
After tax interest on convertible debt	15		13		30		25
Net income — diluted	$	103,254	$	68,494	$	185,257	$	243,208
Weighted average shares (denominator):
Weighted average shares — basic	182,637		187,597		183,877		187,927
Stock options	4,265		4,333		4,391		4,389
Restricted stock units	165		87		158		74
Convertible debt	121		121		121		121
Weighted average shares — diluted	187,188		192,138		188,547		192,511
Net income per share:
Basic	$	0.57	$	0.37	$	1.01	$	1.29
Diluted	$	0.55	$	0.36	$	0.98	$	1.26

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]

	Three Months Ended		Six Months Ended
	June 30,		June 30,
	2018	2017	2018	2017
	(In thousands)		(In thousands)
Antidilutive options	1,155	1,523	868	1,212