Commitments and Contingencies - Additional Information (Detail) - USD ($)	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Commitments Contingencies And Litigation [Line Items]
Annual royalty expenses	$ 2,579,000	$ 2,600,000	$ 3,134,000
2019	11,271,000
2020 - 2023	127,000
Thereafter	0
Expenses under operating leases	2,457,000	2,140,000	$ 1,966,000
2019	1,866,000
2020	1,700,000
2021	1,461,000
2022	978,000
2023	876,000
Payments for indemnifications	0	0
Liabilities for indemnifications	$ 0	$ 0
Diagnostics [Member]
Commitments Contingencies And Litigation [Line Items]
Percentage of total royalty expense	86.00%
Diagnostics [Member] \| Minimum [Member]
Commitments Contingencies And Litigation [Line Items]
Percentage of royalty payable	4.00%
Diagnostics [Member] \| Maximum [Member]
Commitments Contingencies And Litigation [Line Items]
Percentage of royalty payable	8.00%

Amount of loss contingency liability expected to be resolved within one year or the normal operating cycle, if longer.

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Amount of cash outflow reducing loss contingency liability.

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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.

+ References

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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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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 fourth 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 in the third 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 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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Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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Amount of expense related to royalty payments under a contractual arrangement such as payment for mineral and drilling rights and use of technology or intellectual property.

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-Publisher FASB
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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing 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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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing 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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Commitments Contingencies And Litigation [Line Items]

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Percentage of royalty expense.

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Royalty payable as percentage of commercial sales.

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Unrecorded Unconditional Purchase Obligation Balance Due Between Two Through Five Years

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