Taxes on Income 1 (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Current:
Federal	$ 4,637	$ 1,963	$ (44,060)
State	(4,395)	(2,352)	(5,250)
Total current	242	(389)	(49,310)
Deferred:
Federal	95,972	93,330	108,956
State	7,566	14,088	12,254
Total deferred	103,538	107,418	121,210
Actual income tax expense from continuing operations	$ 103,780	$ 107,029	$ 71,900
Effective tax rate	29.00%	31.00%	29.00%

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