Unaudited Condensed Consolidated Statement Of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 71,925	$ 89,981	$ 228,622	$ 248,331
Other comprehensive gains (losses), net of tax:
Unrealized holding gain (loss)	96	51	(1,228)	3
Loss reclassified to net income	363	441	1,284	1,316
Total other comprehensive gain, net of tax	459	492	56	1,319
Comprehensive income	$ 72,384	$ 90,473	$ 228,678	$ 249,650