Business Combinations - Schedule of Intangible Assets Acquired (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Jun. 30, 2019	Sep. 30, 2018
Customer relationships
Acquired Indefinite-lived Intangible Assets [Line Items]
Amortization Period	4 years 9 months 18 days	4 years 9 months 18 days
A2iA
Acquired Indefinite-lived Intangible Assets [Line Items]
Amount assigned		$ 28,610
A2iA | Completed technologies
Acquired Indefinite-lived Intangible Assets [Line Items]
Amortization Period		7 years
Amount assigned		$ 13,015
A2iA | Customer relationships
Acquired Indefinite-lived Intangible Assets [Line Items]
Amortization Period		5 years
Amount assigned		$ 15,360
A2iA | Trade names
Acquired Indefinite-lived Intangible Assets [Line Items]
Amortization Period		5 years
Amount assigned		$ 235
ICAR
Acquired Indefinite-lived Intangible Assets [Line Items]
Amount assigned		$ 6,407
ICAR | Completed technologies
Acquired Indefinite-lived Intangible Assets [Line Items]
Amortization Period		5 years
Amount assigned		$ 4,956
ICAR | Customer relationships
Acquired Indefinite-lived Intangible Assets [Line Items]
Amortization Period		2 years
Amount assigned		$ 1,298
ICAR | Trade names
Acquired Indefinite-lived Intangible Assets [Line Items]
Amortization Period		3 years
Amount assigned		$ 153