Business Segment Information (Summary Of Intercompany Segment Revenues) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Intercompany segment revenues	$ 32,059	$ 26,037	$ 66,783	$ 50,396
Contracting Services [Member]
Intercompany segment revenues	20,538	14,295	43,739	27,164
Production Facilities [Member]
Intercompany segment revenues	$ 11,521	$ 11,742	$ 23,044	$ 23,232

Amount of revenue from transactions with other operating segments of the same entity.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 131

-Paragraph 27

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration