Taxes on Income 2 (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Deferred income tax assets:
Alternative minimum tax credit	$ 38,391	$ 36,526
Other postretirement benefits	21,837	20,206
Pension benefits	32,495	23,491
Derivative financial instruments (interest rates)	32,057	13,571
Net operating loss	24,750	0
Other	34,566	39,245
Total deferred income tax assets	184,096	133,039
Deferred income tax liabilities:
Property, plant and equipment	(1,139,135)	(1,032,473)
Unconsolidated investments (Citrus)	(29,059)	(19,177)
Goodwill	(16,718)	(16,952)
Environmental reserve	(11,641)	(9,374)
Other	(19,268)	(32,296)
Total deferred income tax liability	(1,215,821)	(1,110,272)
Net deferred income tax liability	(1,031,725)	(977,233)
Less current income tax assets (liabilities)	$ 13,152	$ 36,630