Condensed Consolidated Statements of Operations Parenthetical (USD $)	3 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Depreciation:
Net of (gains) on sale of real and personal property	$ (9,710,000)	$ (8,388,000)
Related Party
Related party revenues, net of eliminations	10,900,000	10,700,000
Related party, costs and expenses, net of eliminations	$ 11,300,000	$ 10,700,000

The gains (losses) included in earnings resulting from the sale or disposal of tangible assets. This item does not include any gain (loss) recognized on the sale of oil and gas property or timber property.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 144
-Paragraph 47
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6391110&loc=d3e2941-110230

Reference 3: 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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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