Equity (Schedule of Stock-based Compensation Expense - by Award Type) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Expense:
Stock-based compensation expense	$ 7,756	$ 7,428	$ 9,860
Employee stock options
Expense:
Stock-based compensation expense	2,563	5,147	8,220
Restricted stock awards and units
Expense:
Stock-based compensation expense	3,211	557	0
Employee stock purchase plan
Expense:
Stock-based compensation expense	666	600	551
401(k) match in common stock
Expense:
Stock-based compensation expense	1,034	935	864
Outside director fees in common stock
Expense:
Stock-based compensation expense	$ 282	$ 189	$ 225