Shareholders' Equity and Share-based Compensation - Share-based Compensation (Details) - USD ($)	3 Months Ended			12 Months Ended	119 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018	Jun. 30, 2020	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense	$ 2,876,000	$ 2,369,000
Repurchase of common shares under shares repurchase program	0				6,784,648
Options outstanding, Weighted-Average Remaining Contractual Life (in years)	2 years 7 months 20 days			2 years 10 months 20 days
Options vested and expected to vest (in shares)	643,978				643,978
Options vested and expected to vest (in dollars per share)	$ 8.79				$ 8.79
Options vested and expected to vest, Weighted Average Remaining Contractual Life (in years)	2 years 7 months 20 days
Options vested and expected to vest, Aggregate Intrinsic Value	$ 2,593,702				$ 2,593,702
Exercisable at end of period (in shares)	643,978				643,978
Exercisable at end of period (in dollars per share)	$ 8.79				$ 8.79
Exercisable at end of period, Weighted Average Remaining Contractual Life (in years)	2 years 7 months 20 days
Exercisable at end of period, Aggregate Intrinsic Value	$ 2,593,702				$ 2,593,702
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding at beginning of period (in shares)	643,978
Outstanding at end of period (In shares)	643,978			643,978	643,978
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Outstanding at beginning of period (in dollars per share)	$ 8.79
Outstanding at end of period (in dollars per share)	$ 8.79			$ 8.79	$ 8.79
Options outstanding, Aggregate Intrinsic Value	$ 2,593,702			$ 1,544,664	$ 2,593,702
Market-based Restricted Stock Units (MSU) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense	200,000	200,000
Granted (in shares)			1,300,000
Performance Based Restricted Stock Units (PRSUs) Member
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense	$ 400,000	$ 200,000