Valuation and Qualifying Accounts (Details) - Allowance for Doubtful Accounts - USD ($) $ in Thousands		12 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Movement in Valuation Allowances and Reserves
Balance at beginning of year		$ 6,992	$ 5,519	$ 3,588
Charged to costs and expenses		13,498	13,149	9,584
Other	[1]	(14,891)	(11,676)	(7,653)
Balance at end of year		$ 5,599	$ 6,992	$ 5,519

[1] Uncollectible accounts written off, net of recoveries