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

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 144

-Paragraph 45, 46, 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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 45

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=8077374&loc=d3e2420-110228

Name:	us-gaap_AssetImpairmentCharges
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Impairment Charges (Details) (USD $)	12 Months Ended		3 Months Ended				1 Months Ended	3 Months Ended
Impairment Charges (Details) (USD $)	Dec. 31, 2011	Dec. 31, 2010	Sep. 30, 2011 Nashville facility	Jun. 30, 2010 Gateway facility	Dec. 31, 2012 Gateway facility NASCAR Nationwide Series events item	Dec. 31, 2012 Gateway facility NASCAR Camping World Truck Series events item	Jan. 31, 2011 Memphis Motorsports Park facility	Dec. 31, 2010 Memphis Motorsports Park facility
Impairment Charges
Carrying Value of Long-Lived Assets			$ 46,016,000	$ 9,464,000
Fair Value of Long-Lived Assets			30,329,000	1,500,000
Non-cash impairment charge	15,687,000	809,000	15,687,000	7,964,000				809,000
Number of events for which sanction agreements will not be sought					2	1
Net proceeds after closing costs from sale of facility and all personal property at the facility							$ 2,000,000