Annual report pursuant to Section 13 and 15(d)

Related Parties - Additional Information (Detail)

v2.4.0.8
Related Parties - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Oil Chem Research Company [Member]
     
Related Party Transaction [Line Items]      
Purchase from related party $ 2.0 $ 2.0 $ 1.5
SFC [Member]
     
Related Party Transaction [Line Items]      
Aggregate annual rent for leased aircraft usage 0.9 0.9 0.6
Speedway Motorsports, Inc. [Member]
     
Related Party Transaction [Line Items]      
Purchase from related party 0.7 0.6 0.6
Sales to related party 0.1 0.2 0.3
Subsidiary of SFC [Member]
     
Related Party Transaction [Line Items]      
Aggregate annual rent for leased aircraft usage     $ 0.4