Equity (Schedule of Stock-based Compensation Expense - by Award Type) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012
Expense:
Stock-based compensation expense	$ 1,051	$ 2,542	$ 2,133	$ 4,722
Employee stock options
Expense:
Stock-based compensation expense	123	1,088	381	2,135
Restricted stock awards and units
Expense:
Stock-based compensation expense	515	946	921	1,521
Employee stock purchase plan
Expense:
Stock-based compensation expense	125	189	256	413
401(k) match in common stock
Expense:
Stock-based compensation expense	257	245	513	475
Outside director fees in common stock
Expense:
Stock-based compensation expense	$ 31	$ 74	$ 62	$ 178