Equity (Schedule of Common Stock Reserved for Future Issuances) (Details) - shares	Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise of outstanding stock options (in shares)	51,854	69,980
Purchases under the employee stock purchase plan (in shares)	543,731
Issuance of stock-based awards under the Equity Plans (in shares)	2,753,829
Purchases under the officer and director share purchase plan (in shares)	88,741
Total reserved (in shares)	5,455,870
Restricted stock units and awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested stock units (in shares)	1,007,401
Performance Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested award potential, percentage	200.00%
Unvested stock units (in shares)	471,824	397,777
Unvested performance stock units (in shares)	1,010,314