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Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2011

Earnings Per Share [Abstract]

Calculated Basic And Diluted Earnings Per Share

		Years Ended December 31
		2011				2010				2009
Basic earnings per share
Numerator:
Net income		$	206,907			$	177,125			$	162,283
Denominator:
Weighted-average number of shares of common stock outstanding			13,707				14,619				15,206
Basic earnings per share		$	15.10			$	12.12			$	10.67
Diluted earnings per share
Numerator:
Net income		$	206,907			$	177,125			$	162,283
Denominator:
Weighted-average number of shares of common stock outstanding			13,707				14,619				15,206
Shares issuable upon exercise of stock options			5				31				37
Total shares			13,712				14,650				15,243
Diluted earnings per share		$	15.09			$	12.09			$	10.65

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- Definition

Tabular disclosure of an entity's basic and diluted earnings per share calculations.

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No definition available.

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