CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
CASH PROVIDED BY OPERATIONS:
Net income	$ 252,576	$ 180,602	$ 736,841
Adjustments to reconcile net income to net cash provided by operations:
Depreciation and amortization	271,008	247,900	204,872
Provision for pension and postretirement benefits	32,010	39,484	20,115
Share-based compensation expense	33,931	24,808	22,088
Postretirement benefit claims paid	(3,470)	(3,811)	(2,926)
Gain on disposals of property, plant and equipment	(20,119)	(2,502)	(4,100)
Deferred income taxes	(33,559)	(4,649)	(21,492)
Contributions to pension plans	(18,860)	(42,055)	(53,394)
Gain on sale of land drilling operations	0	0	(212,891)
Gain on sale of manufacturing operations	0	0	(670,614)
Write-off of deferred debt issuance costs	0	690	0
Material charges	4,453	12,038	8,000
Changes in current assets and liabilities:
Receivables - trade and other	30,784	(105,762)	22,825
Inventories	0	0	(104,468)
Prepaid expenses and other current assets	9,583	(9,879)	303
Accounts payable	32,373	(8,608)	44,784
Accrued income taxes	(17,714)	16,210	(6,097)
Deferred revenues	2,175	16,120	41,428
Billings in excess of costs and estimated profits on uncompleted contracts	0	0	29,493
Other current liabilities	(12,441)	17,873	10,263
Net changes in other noncurrent assets and liabilities	60,446	15,250	29,649
Net cash provided by operations	623,176	393,709	94,679
CASH PROVIDED BY (USED IN) INVESTING ACTIVITIES:
Capital expenditures	(607,311)	(685,256)	(1,517,674)
Proceeds from sale of manufacturing operations, net	0	0	1,041,861
Proceeds from sale of land drilling operations, net	0	0	513,619
Decrease in restricted cash	0	0	15,265
Proceeds from disposals of property, plant and equipment	44,550	10,500	5,734
Net cash provided by (used in) investing activities	(562,761)	(674,756)	58,805
CASH PROVIDED BY (USED IN) FINANCING ACTIVITIES:
Proceeds from borrowings	0	1,104,929	0
Debt issue costs	0	(2,026)	0
Repayments of borrowings	0	(238,453)	(52,166)
Proceeds from exercise of share options	2,911	588	19,941
Excess tax benefits from share-based compensation	3,690	1,164	5,128
Payments to acquire treasury shares	0	0	(125,013)
Other	1,820	0	0
Net cash provided by (used in) financing activities	8,421	866,202	(152,110)
INCREASE IN CASH AND CASH EQUIVALENTS	68,836	585,155	1,374
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	1,024,008	438,853	437,479
CASH AND CASH EQUIVALENTS, END OF PERIOD	$ 1,092,844	$ 1,024,008	$ 438,853