Build-to-Suit Lease - Schedule of Future Sublease Income Term (Detail) $ in Thousands	Dec. 31, 2018 USD ($)
Leases Operating [Abstract]
2019	$ 2,068
2020	2,479
2021	2,544
2022	2,611
2023	2,680
Thereafter	2,284
Total	$ 14,666

Operating leases future minimum payments receivable sublease rentals current.

No definition available.

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Operating leases future minimum payments receivable sublease rentals due.

No definition available.

Name:	arav_OperatingLeasesFutureMinimumPaymentsReceivableSubleaseRentalsDue
Namespace Prefix:	arav_
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Operating leases future minimum payments receivable sublease rentals in five years.

No definition available.

Name:	arav_OperatingLeasesFutureMinimumPaymentsReceivableSubleaseRentalsInFiveYears
Namespace Prefix:	arav_
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Operating leases future minimum payments receivable sublease rentals in four years.

No definition available.

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Namespace Prefix:	arav_
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Operating leases future minimum payments receivable sublease rentals in three years.

No definition available.

Name:	arav_OperatingLeasesFutureMinimumPaymentsReceivableSubleaseRentalsInThreeYears
Namespace Prefix:	arav_
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Operating leases future minimum payments receivable sublease rentals in two years.

No definition available.

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Namespace Prefix:	arav_
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Operating leases future minimum payments receivable sublease rentals thereafter.

No definition available.

Name:	arav_OperatingLeasesFutureMinimumPaymentsReceivableSubleaseRentalsThereafter
Namespace Prefix:	arav_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

No definition available.

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