Commitments and Contingencies - Future Minimum Lease Commitments on Non-Cancelable Operating Leases, Lease Income and Sublease Income (Details) $ in Thousands	Sep. 30, 2018 USD ($)
Gross Payments
2019	$ 3,842
2020	2,377
2021	1,545
2022	1,370
2023	1,251
Thereafter	1,847
Gross Payments	12,232
Scheduled Sublease Payments
2019	9
Scheduled Sublease Payments	9
Net Payments
2019	3,833
2020	2,377
2021	1,545
2022	1,370
2023	1,251
Thereafter	1,847
Operating Leases, Future Minimum Payments Due, Total	$ 12,223

Operating Leases Future Minimum Payments Due Fiscal Year Maturity Gross [Abstract]

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Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Fiscal Year Maturity [Abstract]

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Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Next Twelve Months

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Operating Leases, Future Minimum Payments, Gross, Due in Five Years

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Contractually required future rental payments receivable on noncancelable subleasing arrangements.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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