XML 23 R43.htm IDEA: XBRL DOCUMENT v2.3.0.15

Property and Equipment - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2011 Rigs	Sep. 30, 2010 Rigs
Property, Plant, and Equipment Disclosure [Line Items]
Number of drilling rigs that would no longer be marketed as rigs	22	4
Impairment charges on drilling rigs	$ 4.3	$ 4.2

X

- Definition

Number of Rigs

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Namespace Prefix:	pten
Data Type:	xbrli:integerItemType
Balance Type:	na
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X

- Definition

Property, Plant, and Equipment Disclosure [Line Items]

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- Definition

The charge against earnings resulting from the aggregate write down of tangible assets from their carrying value to their fair value.

+ References

Reference 1: 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



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6391110&loc=d3e2921-110230

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