Intangible Assets - Gross Carrying Amounts and Accumulated Amortization (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Sep. 30, 2016
Gross carrying amount and accumulated amortization of intangible assets
Total Gross Carrying Amount	$ 502,024		$ 507,967
Accumulated Amortization	192,410		188,805
Amortization expense related to intangible assets	6,300	$ 4,600
Trade names
Gross carrying amount and accumulated amortization of intangible assets
Gross Carrying Amount	$ 62,474		63,245
Intellectual property
Gross carrying amount and accumulated amortization of intangible assets
Estimated useful lives	20 years
Gross Carrying Amount	$ 10,026		10,102
Accumulated Amortization	528
Contracts
Gross carrying amount and accumulated amortization of intangible assets
Gross Carrying Amount	124,920		127,520
Accumulated Amortization	75,067		76,029
Customer relationships
Gross carrying amount and accumulated amortization of intangible assets
Gross Carrying Amount	225,339		227,909
Accumulated Amortization	$ 70,522		67,493
Trade names
Gross carrying amount and accumulated amortization of intangible assets
Estimated useful lives	20 years
Gross Carrying Amount	$ 66,755		66,755
Accumulated Amortization	40,579		39,744
Patents and Patented Technologies
Gross carrying amount and accumulated amortization of intangible assets
Gross Carrying Amount	5,401		5,401
Accumulated Amortization	2,931		2,875
Other
Gross carrying amount and accumulated amortization of intangible assets
Gross Carrying Amount	7,109		7,035
Accumulated Amortization	$ 2,783		$ 2,664
Minimum | Contracts
Gross carrying amount and accumulated amortization of intangible assets
Estimated useful lives	15 years
Minimum | Customer relationships
Gross carrying amount and accumulated amortization of intangible assets
Estimated useful lives	5 years
Minimum | Patents and Patented Technologies
Gross carrying amount and accumulated amortization of intangible assets
Estimated useful lives	6 years
Minimum | Other
Gross carrying amount and accumulated amortization of intangible assets
Estimated useful lives	5 years
Maximum | Contracts
Gross carrying amount and accumulated amortization of intangible assets
Estimated useful lives	20 years
Maximum | Customer relationships
Gross carrying amount and accumulated amortization of intangible assets
Estimated useful lives	20 years
Maximum | Patents and Patented Technologies
Gross carrying amount and accumulated amortization of intangible assets
Estimated useful lives	19 years
Maximum | Other
Gross carrying amount and accumulated amortization of intangible assets
Estimated useful lives	17 years