XML 15 R46.htm IDEA: XBRL DOCUMENT v2.4.0.6

Major Lessees (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Alpha Natural Resources [Member]
Revenues from lessees that exceeded ten percent of total revenues
Revenues	$ 24,148	$ 24,842
Percent	26.00%	29.00%
The Cline Group [Member]
Revenues from lessees that exceeded ten percent of total revenues
Revenues	$ 23,715	$ 14,430
Percent	26.00%	17.00%

X

- Definition

Percentage of revenues from lessees exceeding ten percent of revenues.

+ References

No definition available.

+ Details

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X

- Definition

The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 19

-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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 25

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6453417&loc=d3e39896-112707

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