Fair Value Measurements (Details) (USD $)	12 Months Ended
	Sep. 30, 2013 Equity investments (A) item	Sep. 30, 2013 Recurring basis Level 1	Sep. 30, 2012 Recurring basis Level 1	Sep. 30, 2013 Recurring basis Level 1 Money market accounts	Sep. 30, 2012 Recurring basis Level 1 Money market accounts	Sep. 30, 2013 Recurring basis Level 1 Certificates of deposit	Sep. 30, 2012 Recurring basis Level 1 Certificates of deposit	Sep. 30, 2013 Recurring basis Level 1 Equity investments (A)	Sep. 30, 2012 Recurring basis Level 1 Equity investments (A)	Sep. 30, 2013 Recurring basis Level 1 Assets held in trust for deferred compensation plan (B)	Sep. 30, 2012 Recurring basis Level 1 Assets held in trust for deferred compensation plan (B)	Sep. 30, 2013 Recurring basis Level 2	Sep. 30, 2012 Recurring basis Level 2	Sep. 30, 2013 Recurring basis Level 2 Money market accounts	Sep. 30, 2012 Recurring basis Level 2 Money market accounts	Sep. 30, 2013 Recurring basis Level 2 Certificates of deposit	Sep. 30, 2012 Recurring basis Level 2 Certificates of deposit	Sep. 30, 2013 Recurring basis Level 2 Equity investments (A)	Sep. 30, 2012 Recurring basis Level 2 Equity investments (A)	Sep. 30, 2013 Recurring basis Level 2 Assets held in trust for deferred compensation plan (B)	Sep. 30, 2012 Recurring basis Level 2 Assets held in trust for deferred compensation plan (B)	Sep. 30, 2013 Recurring basis Level 3	Sep. 30, 2012 Recurring basis Level 3	Sep. 30, 2013 Recurring basis Level 3 Money market accounts	Sep. 30, 2012 Recurring basis Level 3 Money market accounts	Sep. 30, 2013 Recurring basis Level 3 Certificates of deposit	Sep. 30, 2012 Recurring basis Level 3 Certificates of deposit	Sep. 30, 2013 Recurring basis Level 3 Equity investments (A)	Sep. 30, 2012 Recurring basis Level 3 Equity investments (A)	Sep. 30, 2013 Recurring basis Level 3 Assets held in trust for deferred compensation plan (B)	Sep. 30, 2012 Recurring basis Level 3 Assets held in trust for deferred compensation plan (B)	Sep. 30, 2013 Recurring basis Total Fair Value	Sep. 30, 2012 Recurring basis Total Fair Value	Sep. 30, 2013 Recurring basis Total Fair Value Money market accounts	Sep. 30, 2012 Recurring basis Total Fair Value Money market accounts	Sep. 30, 2013 Recurring basis Total Fair Value Certificates of deposit	Sep. 30, 2012 Recurring basis Total Fair Value Certificates of deposit	Sep. 30, 2013 Recurring basis Total Fair Value Equity investments (A)	Sep. 30, 2012 Recurring basis Total Fair Value Equity investments (A)	Sep. 30, 2013 Recurring basis Total Fair Value Assets held in trust for deferred compensation plan (B)	Sep. 30, 2012 Recurring basis Total Fair Value Assets held in trust for deferred compensation plan (B)
Fair Value Measurements
Liabilities Fair Value																																$ 0
Assets Fair Value		$ 27,335,000	$ 29,087,000	$ 26,845,000	$ 28,591,000	$ 0	$ 0	$ 0	$ 0	$ 490,000	$ 496,000	$ 4,340,000	$ 4,496,000	$ 0	$ 0	$ 4,340,000	$ 4,496,000	$ 0	$ 0	$ 0	$ 0	$ 8,875,000	$ 5,166,000	$ 0	$ 0	$ 0	$ 0	$ 8,875,000	$ 5,166,000	$ 0	$ 0	$ 40,550,000	$ 38,749,000	$ 26,845,000	$ 28,591,000	$ 4,340,000	$ 4,496,000	$ 8,875,000	$ 5,166,000	$ 490,000	$ 496,000
Number of privately held companies in which the entity has made equity investments	3