Stock-Based Compensation - Schedule of Stock Option Activity and Weighted Average Exercise Prices (Details) - Employee Stock Option $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($) $ / shares shares
Options
Outstanding at January 1, 2018 (in shares) | shares	792,943
Granted (in shares) | shares	0
Forfeited or expired (in shares) | shares	(65,868)
Exercised (in shares) | shares	(8,513)
Outstanding at September 30, 2018 (in shares) | shares	718,562
Options exercisable at September 30, 2018 (in shares) | shares	540,597
Weighted- Average Exercise Price
Outstanding at January 1, 2018 (in dollars per share) | $ / shares	$ 47.59
Granted (in dollars per share) | $ / shares	0
Forfeited or expired (in dollars per share) | $ / shares	54.23
Exercised (in dollars per share) | $ / shares	34.18
Outstanding at September 30, 2018 (in dollars per share) | $ / shares	47.38
Options exercisable at September 30, 2018 (in dollars per share) | $ / shares	$ 46.57
Weighted-Average Remaining Contractual Term (Years)
Weighted-average remaining contractual term, outstanding at September 30, 2018	4 years 3 months 18 days
Weighted-average remaining contractual term, options exercisable at September 30, 2018	2 years 7 months 6 days
Aggregate Intrinsic Value as of March 31, 2019
Aggregate intrinsic value outstanding at September 30, 2018 | $	$ 3,118
Aggregate intrinsic value of options exercisable at September 30, 2018 | $	$ 2,410