Shareholders' Equity (Market prices per share on a national securities exchange as vesting condition) (Details) (USD $)	9 Months Ended
	Jun. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock units subject to vesting conditions	660,630
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock units subject to vesting conditions	660,630
Third Anniversary | Seventeen Dollars And Fifty Cents Per Share Market Price
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock units subject to vesting conditions	166,500
Weighted average fair value per share restricted stock	$ 17.50
Fourth Anniversary | Ten Dollar Per Share Market Price
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock units subject to vesting conditions	189,273
Weighted average fair value per share restricted stock	$ 10
Fourth Anniversary | Seventeen Dollars And Fifty Cents Per Share Market Price
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock units subject to vesting conditions	112,171
Weighted average fair value per share restricted stock	$ 17.50
Fourth Anniversary | Twenty Dollar Per Share Market Price
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock units subject to vesting conditions	8,500
Weighted average fair value per share restricted stock	$ 20
Fourth Anniversary | Twenty Two Dollars And Fifty Cents Per Share Market Price
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock units subject to vesting conditions	19,000
Weighted average fair value per share restricted stock	$ 22.50
Fifth Anniversary | Ten Dollar Per Share Market Price
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock units subject to vesting conditions	103,513
Weighted average fair value per share restricted stock	$ 10
Fifth Anniversary | Seventeen Dollars And Fifty Cents Per Share Market Price
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock units subject to vesting conditions	30,000
Weighted average fair value per share restricted stock	$ 17.50
No Vesting | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock units subject to vesting conditions	31,673