Other Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Finite-Lived Intangible Assets [Line Items]
Acquired finite-lived intangible assets, weighted average useful life	8 years
Carrying amount, finite-lived intangible assets	$ 472,266	$ 467,455
Accumulated Amortization	(191,706)	(161,254)
Total	280,560	306,201
Indefinite‑lived intangible assets	34,207	34,207
Carrying amount, intangible assets	506,473	501,662
Intangible assets, net	$ 314,767	340,408
Customer related
Finite-Lived Intangible Assets [Line Items]
Acquired finite-lived intangible assets, weighted average useful life	11 years
Carrying amount, finite-lived intangible assets	$ 290,407	292,115
Accumulated Amortization	(64,548)	(47,348)
Total	$ 225,859	244,767
Proprietary technology
Finite-Lived Intangible Assets [Line Items]
Acquired finite-lived intangible assets, weighted average useful life	5 years
Carrying amount, finite-lived intangible assets	$ 50,725	49,315
Accumulated Amortization	(24,187)	(19,685)
Total	$ 26,538	$ 29,630
Finite-lived intangible asset, useful life	10 years	10 years
Trademark
Finite-Lived Intangible Assets [Line Items]
Acquired finite-lived intangible assets, weighted average useful life	7 years
Carrying amount, finite-lived intangible assets	$ 26,432	$ 26,535
Accumulated Amortization	(6,245)	(3,563)
Total	20,187	22,972
Backlog
Finite-Lived Intangible Assets [Line Items]
Carrying amount, finite-lived intangible assets	81,834	82,315
Accumulated Amortization	(81,834)	(81,764)
Total	$ 0	$ 551
Finite-lived intangible asset, useful life	1 year	1 year
Other
Finite-Lived Intangible Assets [Line Items]
Acquired finite-lived intangible assets, weighted average useful life	2 years
Carrying amount, finite-lived intangible assets	$ 22,868	$ 17,175
Accumulated Amortization	(14,892)	(8,894)
Total	$ 7,976	$ 8,281
Finite-lived intangible asset, useful life	3 years	4 years
Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	1 year
Minimum [Member] | Customer related
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	5 years	5 years
Minimum [Member] | Trademark
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	10 years	10 years
Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	26 years
Maximum [Member] | Customer related
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	26 years	26 years
Maximum [Member] | Trademark
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	15 years	15 years