Basis of Presentation (Tables)

6 Months Ended

Jun. 30, 2012

Basis of Presentation [Abstract]

Summary of the effects of the correction of errors on the Condensed Consolidated Balance Sheet

	As of June 30, 2011
in thousands	As Reported		Correction			As Restated
Balance Sheet
Assets
Current deferred income taxes		$44,794		$910			$45,704
Prepaid expenses		21,659		735			22,394
Total current assets		892,353		1,645			893,998
Total assets		$8,385,610		$1,645			$8,387,255
Liabilities
Other current liabilities		$162,001		$16,676			$178,677
Total current liabilities		420,960		16,676			437,636
Noncurrent deferred income taxes		762,406		(5,849	)		756,557
Total liabilities		$4,504,345		$10,827			$4,515,172
Equity
Retained earnings		$1,385,208		($9,182	)		$1,376,026
Total equity		3,881,265		(9,182	)		3,872,083
Total liabilities and equity		$8,385,610		$1,645			$8,387,255