Segment Information (Details 1) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Reconciliation of total adjusted segment income to consolidated income from continuing operations before income taxes
Adjusted segment income	$ 61,391	$ 47,445	$ 116,303	$ 85,070
Gain on debt repurchase		422		1,027
Income from continuing operations before income taxes	$ 61,391	$ 47,867	$ 116,303	$ 86,097

Amount represents the difference between the fair value of the payments made and the carrying amount of the debt at the time of its extinguishment.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 26
-Paragraph 20, 21

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