Discontinued Operations - Additional Information (Details) (LeTourneau Technologies, Inc., USD $)	0 Months Ended	12 Months Ended
Oct. 24, 2011	Oct. 26, 2012
LeTourneau Technologies, Inc.
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of LeTourneau Technologies Drilling Systems, Inc.	$ 375,000,000
Payment for post closing working capital adjustment		56,300,000
Loss on sale of supply agreements	$ 23,300,000

Amount of gain (loss), after tax expense or benefit and not previously recognized, resulting from the sale of a business component.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 45

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e957-107759

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

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