Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Operating activities:
Net income	$ 774,052	$ 713,770
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	303,523	297,265
Gain on disposition of assets	(4,344)	(33,425)
(Gain) loss on sale of marketable securities, net	(780)	5
Gain on foreign currency forward exchange contracts	(9,593)	(1,924)
Deferred tax provision	(15,798)	14,918
Accretion of discounts on marketable securities	(39)	(421)
Amortization of debt issuance costs	659	665
Amortization of debt discounts	172	222
Stock-based compensation expense	3,749	4,821
Deferred income, net	(46,127)	41,768
Deferred expenses, net	62,836	(77,372)
Other assets, noncurrent	(165)	7,804
Other liabilities, noncurrent	964	10,413
Proceeds from settlement of foreign currency forward exchange contracts designated as accounting hedges	9,593	1,924
Changes in operating assets and liabilities:
Accounts receivable	20,055	141,726
Prepaid expenses and other current assets	(20,137)	(16,023)
Accounts payable and accrued liabilities	(43,845)	10,146
Taxes payable	44,368	(166,389)
Net cash provided by operating activities	1,079,143	949,893
Investing activities:
Capital expenditures (including rig construction)	(643,305)	(312,995)
Proceeds from disposition of assets, net of disposal costs	5,128	186,333
Proceeds from sale and maturities of marketable securities	4,862,108	3,700,176
Purchases of marketable securities	(5,051,538)	(4,099,525)
Net cash used in investing activities	(827,607)	(526,011)
Financing activities:
Redemption of zero coupon debentures		(4,238)
Payment of dividends	(367,930)	(611,668)
Other	4	41
Net cash used in financing activities	(367,926)	(615,865)
Net change in cash and cash equivalents	(116,390)	(191,983)
Cash and cash equivalents, beginning of period	464,393	376,417
Cash and cash equivalents, end of period	$ 348,003	$ 184,434