Supplemental Balance Sheet Income Statement and Cash Flow Information (Details 3) (USD $) In Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Impairments and other charges
Provision for retirement of long-lived assets		$ 23,200	$ 98,072	$ 23,213
Impairment of long-lived assets			98,100	34,832
Impairment of oil and gas-related assets		54,300	0	54,347
Goodwill impairments		10,700	0	10,707
Impairments and other charges	$ 98,072	$ 123,099	$ 98,072	$ 123,099