Goodwill and Intangible Assets Goodwill and Intangible Assets - Estimated Amortization Expense (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Sep. 30, 2018
Finite-Lived Intangible Assets [Line Items]
2015	$ 94,308
2016	81,177
2017	71,849
2018	53,092
2019	27,850
Thereafter	28,656
Total	356,932	$ 450,001
Cost of Revenue
Finite-Lived Intangible Assets [Line Items]
2015	33,628
2016	25,286
2017	20,019
2018	13,507
2019	5,041
Thereafter	0
Total	97,481
Operating Expense [Member]
Finite-Lived Intangible Assets [Line Items]
2015	60,680
2016	55,891
2017	51,830
2018	39,585
2019	22,809
Thereafter	28,656
Total	$ 259,451