Leases - Future minimum lease payments (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Lessee, Lease, Description [Line Items]
2021		$ 21,017
2022		20,416
2023		19,370
2024		18,071
2025		15,718
Thereafter		105,544
Total minimum lease payments		200,136
2021		243
2022		248
2023		253
2024		258
2025		263
Thereafter		4,343
Total minimum lease payments		5,608
Less amount representing interest		$ 3,018
Present value of net minimum lease payments	$ 2,590
Vehicles
Lessee, Lease, Description [Line Items]
2020	17,600
2021	18,000
2022	11,800
2023	8,500
2024	5,400
Thereafter	$ 2,700

Operating Leases, Expected Minimum Payments Due, Due Thereafter

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Amount of minimum lease payments for capital leases.

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Amount necessary to reduce net minimum lease payments to present value for capital leases.

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Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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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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