Cash Dividends (Details) (USD $)	0 Months Ended			3 Months Ended		6 Months Ended
	Mar. 06, 2013	Mar. 01, 2013	Dec. 04, 2012	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012
Cash Dividends
Cash dividends, per share (in dollars per share)	$ 0.15		$ 0.15	$ 0.15	$ 0.07	$ 0.30	$ 0.14
Cash dividend paid, per share (in dollars per share)		$ 0.15