Comprehensive Income (Details) - USD ($) $ in Thousands	May. 31, 2015	Nov. 30, 2014
Statement of Comprehensive Income [Abstract]
Terminated interest rate swap, net of tax benefit of $2,600 and $2,388, respectively	$ 3,652	$ 3,981
Accumulated other comprehensive income (loss), terminated interest rate swap, tax	$ 2,388	$ 2,600

Accumulated Other Comprehensive Income (Loss), Terminated Interest Rate Swap, Net of Tax

No definition available.

Name:	isca_AccumulatedOtherComprehensiveIncomeLossTerminatedInterestRateSwapNetOfTax
Namespace Prefix:	isca_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant