Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2011

Earnings Per Share

Computation of basic and diluted earnings per share

	2011		2010		2009
Numerator (basic and diluted):
Net income	$	507,673	$	419,373	$	307,498
Denominator:
Denominator for basic earnings per share–         weighted-average shares		134,667		138,654		136,230
Effect of stock options (1)		2,316		2,348		1,651
Effect of exchangeable notes		-		990		1
Denominator for diluted earnings per share--         weighted-average shares and assumed conversion		136,983		141,992		137,882
Earnings per share-basic	$	3.77	$	3.02	$	2.26
Earnings per share-assuming dilution	$	3.71	$	2.95	$	2.23

Antidilutive stock option summary

Antidilutive common stock equivalents not included in the calculation of diluted earnings per share:
Stock options (1)		1,756		1,373		1,587
Weighted-average exercise price per share of antidilutive stock options (1)	$	62.79	$	48.15	$	35.61
(1)  See Note 10 for further discussion on the terms of the Company's share-based compensation plans.