Stockholders’ Equity - Narrative (Details)	9 Months Ended	69 Months Ended
	Jun. 30, 2018 item shares	Jun. 30, 2018 shares
RSUs
Stockholders' Equity
Number of units awarded (in shares)		2,258,844
Number of shares of common stock that each award holder has the contingent right to receive	1
Vested awards to date	644,663	644,663
Expected awards vested (in shares)	431,675
Time-based RSUs
Stockholders' Equity
Number of units awarded (in shares)		1,086,380
Number of equal installments for vesting of stock awards | item	4
Performance-based RSUs
Stockholders' Equity
Number of units awarded (in shares)		1,172,464
Vesting period	3 years
Number of vesting criteria which have to be satisfied out of total vesting criteria | item	1
Number of vesting criteria | item	3