Term Loan and Credit Facility - Narrative (Details) - USD ($)		9 Months Ended
Jan. 10, 2020	Sep. 30, 2020
Medium-term Notes \| Term Facility
Debt Instrument [Line Items]
Aggregate principal amount	$ 55,000,000.0
Debt instrument, LIBOR floor	2.00%
Medium-term Notes \| Term Facility \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread (as a percent)	5.75%
Medium-term Notes \| Term Facility \| Debt Instrument, Tranche One
Debt Instrument [Line Items]
Aggregate principal amount	$ 10,000,000.0	$ 10,000,000
Proceeds from issuance of long-term debt		9,800,000
Debt issuance costs		200,000
Estimated fair value		$ 8,200,000
Medium-term Notes \| Term Facility \| Debt Instrument, Tranche Two
Debt Instrument [Line Items]
Aggregate principal amount	15,000,000.0
Medium-term Notes \| Term Facility \| Debt Instrument, Tranche Three
Debt Instrument [Line Items]
Aggregate principal amount	15,000,000.0
Medium-term Notes \| Term Facility \| Debt Instrument, Tranche Four
Debt Instrument [Line Items]
Aggregate principal amount	15,000,000.0
Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 20,000,000.0
Debt instrument, covenant, percent net collectible value of accounts receivable	85.00%
Debt instrument, covenant, percent of eligible inventory	40.00%
Debt instrument, covenant, inventory percentage of availability	20.00%
Potential increase in maximum borrowing capacity	$ 20,000,000.0
Debt instrument, LIBOR floor	2.00%
Line of Credit \| Revolving Credit Facility \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread (as a percent)	3.50%

Debt Instrument, Covenant, Inventory Percentage Of Availability

No definition available.

Name:	rdus_DebtInstrumentCovenantInventoryPercentageOfAvailability
Namespace Prefix:	rdus_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Covenant, Percent Net Collectible Value Of Accounts Receivable

+ References

No definition available.

+ Details

Name:	rdus_DebtInstrumentCovenantPercentNetCollectibleValueOfAccountsReceivable
Namespace Prefix:	rdus_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Covenant, Percent Of Eligible Inventory

+ References

No definition available.

+ Details

Name:	rdus_DebtInstrumentCovenantPercentOfEligibleInventory
Namespace Prefix:	rdus_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, London Interbank Offered Rate (LIBOR) Floor

+ References

No definition available.

+ Details

Name:	rdus_DebtInstrumentLondonInterbankOfferedRateLIBORFloor
Namespace Prefix:	rdus_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of Credit Facility, Accordion Feature, Increase Limit

+ References

No definition available.

+ Details

Name:	rdus_LineOfCreditFacilityAccordionFeatureIncreaseLimit
Namespace Prefix:	rdus_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28555-108399

+ Details

Name:	us-gaap_DeferredFinanceCostsGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

Name:	us-gaap_LongTermDebtFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585

+ Details

Name:	us-gaap_ProceedsFromIssuanceOfLongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_MediumTermNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=rdus_TermFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	rdus_DebtInstrumentBorrowingPeriodAxis=rdus_DebtInstrumentTrancheOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	rdus_DebtInstrumentBorrowingPeriodAxis=rdus_DebtInstrumentTrancheTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	rdus_DebtInstrumentBorrowingPeriodAxis=rdus_DebtInstrumentTrancheThreeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	rdus_DebtInstrumentBorrowingPeriodAxis=rdus_DebtInstrumentTrancheFourMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LineOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: