Earnings Per Common Share (Tables)

6 Months Ended

Jun. 30, 2011

Earnings Per Share [Abstract]

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

The following table provides details of the calculations of basic and diluted earnings per share:

	Three Months Ended June 30,				Six Months Ended June 30,
	2011		2010		2011		2010
Net income	$	56,454	$	38,558	$	114,865	$	95,511
Shares used for determining basic earnings per common share	81,128,442		80,104,004		81,038,096		79,923,790
Dilutive effect of:
Stock options	494,374		374,768		487,376		387,399
Performance and restricted shares	634,627		613,931		611,325		592,281
Assumed conversion of Senior Exchangeable Notes (a)	1,541,395		—		1,271,207		—
Assumed conversion of warrants (a)	328,778		—		104,321		—
Shares used for determining diluted earnings per common share	84,127,616		81,092,703		83,512,325		80,903,470
Basic earnings per common share	$	0.70	$	0.48	$	1.42	$	1.20
Diluted earnings per common share	$	0.67	$	0.48	$	1.38	$	1.18

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

	Three Months Ended June 30,		Six Months Ended June 30,
	2011	2010	2011	2010
Anti-dilutive shares excluded from the computations of
diluted earnings per share:
Stock options, performance and restricted shares	95,772	512,663	131,808	513,567
Exchangeable note hedges (a)	1,541,395	—	1,271,207	—
Total	1,637,167	512,663	1,403,015	513,567

(a) For additional information on the potential dilutive impact of the Senior Exchangeable Notes, warrants and exchangeable note hedges, see Note 11 - Debt in the 2010 Annual Report on Form 10-K.

Schedule of Subsequent Events [Table Text Block]

The following table provides the pro forma post-split basic and dilutive shares used for determining earnings per share:

	Three Months Ended June 30,		Six Months Ended June 30,
	2011	2010	2011	2010
Basic shares	121,692,663	120,156,006	121,557,144	119,885,685
Diluted shares	126,191,424	121,639,055	125,268,488	121,355,205