Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2015

Earnings Per Share [Abstract]

Schedule Of Earnings Per Share Basic And Diluted By Common Class [Table Text Block]

The following table sets forth the computation of basic and diluted earnings per share on net income (in thousands, except per share information):

	2015		2014		2013
Earnings:
Net income (numerator for basic and diluted calculations)	$	502,166	$	684,047	$	418,837
Shares:
Weighted average outstanding shares (denominator for basic calculations)	66,553		69,248		71,917
Equivalent shares from outstanding stock options	739		714		544
Diluted shares (denominator for diluted calculations)	67,292		69,962		72,461
Earnings per share:
Basic	$	7.55	$	9.88	$	5.82
Diluted	7.46		9.78		5.78