Share-based Compensation - Options (Details) - Stock options - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Jun. 30, 2017
Assumptions used to estimate fair values
Risk-free interest rate (as a percent)	1.90%	1.10%
Expected volatility (as a percent)	57.40%	55.60%
Forfeiture rate (as a percent)	6.50%	6.50%
Expected term (in years)	5 years 4 months 24 days	5 years 2 months 12 days
Weighted average fair value (in dollars per share)	$ 9.06	$ 15.33
Awards
Outstanding at the beginning of the period (in shares)	1,475
Granted (in shares)	18
Exercised (in shares)	(14)
Forfeited, expired or repurchased (in shares)	(6)
Outstanding at the end of the period (in shares)	1,473		1,475
Vested and expected to vest, Awards (in shares)	1,470
Exercisable at the end of year (in shares)	1,436
Stock options, Weighted-Average Exercise Price
Outstanding at the beginning of the period (in dollars per share)	$ 18.02
Granted (in dollars per share)	17.40
Exercised (in dollars per share)	6.53
Forfeited, expired or repurchased (in dollars per share)	26.55
Outstanding at the end of the period (in dollars per share)	18.09		$ 18.02
Vested and expected to vest, Weighted-Average Exercise Price (in dollars per share)	18.07
Exercisable at the end of the period (in dollars per share)	$ 17.66
Aggregate Intrinsic Value
Exercised (in dollars)	$ 150
Outstanding at the end of the period (in dollars)	10,075		$ 12,212
Vested and expected to vest, Aggregate Intrinsic Value	10,073
Exercisable at the end of the period (in dollars)	$ 10,057
Weighted Average Remaining Contractual Life (yrs.)
Outstanding at the end of the period (in years)	5 years 6 months		5 years 8 months 12 days
Vested and expected to vest, Weighted Average Remaining Contractual Life	5 years 6 months
Exercisable at the end of the period (in years)	5 years 4 months 24 days