Amount of deferred income and obligation to transfer product and service to customer for which consideration has been received or is receivable.

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-Name Accounting Standards Codification
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Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=121576215&loc=SL77919372-209981

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Contract Revenue and Pass- Through and Other - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation Of Revenue [Line Items]
Deferred revenue	$ 16,000		$ 16,000
Deferred revenue, current	3,760		3,760
Deferred revenue, noncurrent	12,240		12,240
Contract Revenue [Member]
Disaggregation Of Revenue [Line Items]
Lease revenue	52,000	$ 54,500	157,700	$ 164,500
Other Accrued Expenses [Member]
Disaggregation Of Revenue [Line Items]
Deferred revenue, current	$ 3,800		$ 3,800